Answer:
See below this long answer.
Explanation:
These are the main features of the periodic table that you will be able to relate with some property trends of the atoms like size, energy levels, valence electrons, electronegativity, and ionization energy.
A) Features:
1. Elements are arranged in increasing order of atomic number, i.e. number or protons.
2. Since atoms are neutrals, the number of electrons equals the number of protons, and, as result, the elements are arranged in increasing order of number of electrons.
3. The elements are arranged in 18 columns and 7 rows.
4. The rows are named period and correspond to the principal energy level (n): first row corresponds to n = 1, second row corresponds to n = 2, third to n = 3, and so on up to n = 7. The number of elements in each period are:
Period 1, n = 1, 2 elements
Period 2, n = 2, 8 elements
Period 3, n = 3, 8 elements
Period 4, n = 4, 18 elements
Period 5, n = 5, 18 elements
Period 6, n = 6, 32 elements (this includes the 14 lanthanides)
Period 6, n = 7, 32 elements (this includes the 14 lanthanides)
That makes a total of 118 elements.
5. The columns are named groups and they indicate the number of valence electrons
Group 1: 1 valence electron
Group 2: 2 valence electrons
Group 13: 3 valence electrons
Group 14: 4 valence electrons
Group 15: 5 valence electrons
Group 16: 6 valence electrons
Group 17: 7 valence electrons
Group 18: 8 valence electrons
Groups 3 through 12 includ the transition metals and due they have subshells that are not completely filled, their valence electrons vary.
More like a reference than as a rule these are the number of valence electrons for these groups.
Group 3: 3 valence electrons
Group 4: 2-4 valence electrons
Group 5: 2-5 valence electrons
Group 6: 2-6 valence electrons
Group 7: 2-7 valence electrons
Group 8: 2-3 valence electrons
Group 9: 2-3 valence electrons
Group 10: 2-3 valence electrons
Group 11: 1-2 valence electrons
Group 12: 2 valence electrons
B) Property trends
1. Atomic radius (size)
Down a period (from left to right): due to the increase of the positive charge (number of protons) while the main energy level (n) does not change, the electrons in the valence shell feel a stronger atraction to the nucleus causing that the atomic radius decrease from left to right.Down a group (top to bottom): due to the increase of the main energy level, the outermost orbital is bigger and the atoms become bigger. Thus the trend is that the atomic radius increase when you go down a group.2. First ionization energy
Down a period (from left to right): due to the increase of the nuclear charge (such as explained above) the greater attractive force makes that, in general, the first ionization energy increase from left to right.Down a group (top to bottom): due to the increase in the size of the atom, , generally, the energy to remove an electron from the outermost shell, decrease.3. Electronegativity
This is the relative ability to atract electrons in a covalent bond. It increases from left to right and from bottom to top: the most electronegative atoms is fluor.
How many atoms are in 5.4 mol Zn?
Answer: 3.25x10²⁴ atoms Zn
Explanation: Convert moles of Zn to atoms using Avogadro's number
5.4 moles Zn x 6.022x10²³ atoms Zn/ 1 mole Zn
= 3.25x10²⁴ atoms Zn
Question 1 of 10
2 Points
According to Le Châtelier's principle, how will a pressure increase affect a
system that includes matter in the gas phase and another phase?
O
A. The total number of gas molecules will increase.
O
B. The equilibrium reactions will slow down.
C. The system will remain unchanged.
ooo
D. The total number of gas molecules will decrease.
The increase in pressure will result in the decrease of the total number of gas molecules due to the shift in equilibrium toward the side with fewer moles of gas, following Le Châtelier's principle.
Explanation:According to Le Châtelier's principle, how will a pressure increase affect a system that includes matter in the gas phase and another phase? The correct answer is D. The total number of gas molecules will decrease. This is because Le Châtelier's principle states that a pressure increase will shift an equilibrium toward the side of the reaction with the fewer number of moles of gas, as this helps to counteract the change by reducing the pressure within the system. This principle is particularly useful when predicting how a change in pressure will affect the position of equilibrium in a chemical reaction involving gases.
Final answer:
Le Châtelier's principle indicates that increased pressure in a gaseous reaction shifts equilibrium toward the side with fewer gas molecules to reduce the stress caused by the pressure increase.
Explanation:
According to Le Châtelier's principle, a pressure increase in a system involving gases will cause a shift in equilibrium towards the phase with the fewer number of gas molecules. In the case of a reaction with different numbers of gas molecules on each side of the reaction, such as 2NO(g) + O₂(g) ⇒ 2NO₂(g), an increase in pressure would shift the equilibrium towards the formation of NO₂, since it has fewer gas molecules (2) compared to the reactants (3). This phenomenon occurs because the system responds to reduce the pressure by favoring the production of fewer molecules that would occupy less volume.
to what temperature must a sample of nitrogen at 27 degrees C and 0.625atm be taken so that its preassure becomes 1.125atm at constant volume?
Answer:
The sample of nitrogen must be taken to 267 C
what is the appearance of H2o?
Answer:
Water
Explanation:
one molecule of water has two hydrogen atoms covalently bonded to a single oxygen atom. Water is a tasteless, odorless liquid at ambient temperature and pressure. Which is known to be crystal blue.
Answer:
well I t could be in liquid form or in air form
Explanation:
Magnetism easily separates what mixture?
A). Sand and glass
B). Sand and iron
C). Sand and clay
D). Sand and aluminum
Answer:
im pretty sure its b. sand and iron
ik that magnetism easily separates iron
An Apple iPhone has a mass of 112 g. What is its weight in ounces? (Given: 1 lb = 454 g; 1 lb = 16 oz)
Answer:
3.95 oz
General Formulas and Concepts:
Chemistry - Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
Apple iPhone = 112 g
Step 2: Identify Conversions
1 lb = 454 g
1 lb = 16 oz
Step 3: Convert
[tex]112 \ g(\frac{1 \ lb}{454 \ g} )(\frac{16 \ oz}{1 \ lb} )[/tex] = 3.94714 oz
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
3.94714 oz ≈ 3.95 oz
Final answer:
The weight of an Apple iPhone can be calculated by converting the mass from grams to pounds and then from pounds to ounces which results in approximately 3.94 ounces.
Explanation:
To find the weight of an Apple iPhone in ounces, we can use the conversion factors provided. Given that 1 pound (lb) is equal to 16 ounces (oz) and 1 pound (lb) is equivalent to 454 grams (g), we can convert the mass of the iPhone from grams to pounds and then from pounds to ounces.
First, convert the mass of the iPhone from grams to pounds:
112 g ÷ 454 g/lb = 0.246 lb
Next, convert the mass in pounds to ounces:
0.246 lb × 16 oz/lb = 3.9376 oz
Therefore, the weight of the Apple iPhone is approximately 3.94 ounces.
the number of moles of H2O produced from 339 grams of SnO2
Answer:
moles of H2O = 4.5 mol
Explanation:
balanced equation:
SnO2 + 2H2 → Sn + 2H20∴ mass SnO2 = 339 g
∴ molar mass SnO2 = 150.71 g/mol
⇒ moles SnO2 = (339 g)(mol/150.71 g) = 2.25 mol SnO2
⇒ moles H2O = (2.25 mol SnO2)(2 mol H2O/mol SnO2)
⇒ moles H2O = 4.5 mol H2O
If you wanted to repeat your experiment, you could do it once, then do it again, and so on. You could also _____.
Answer:
You can do three experiments and take the average result.
Explanation:
Repeating an experiment establishes two things: reproduciblity and repeatability. These are two different but connected terms.
Reproducibility: This refers to the degree of agreement in the results conducted by different individuals at different locations using different instruments. The experiments are subject to many conditions such as temperature, humidity, human error, instrument error etc.
Repeatability on the other hand, is a measure of how repeatable an experiment is by using same instruments. In other words, the experiment must be replicated elsewhere and still generate the same results or close to that.
To establish the either of the two, three experiments will be sufficient. This means that for the results, there will be a lower value, middle value, and upper value.
The average result is a combination of the results and divided by the number of experiments, in this case, 3.
One advantage of doing 3 experiments is that you get a quick representative of how the results are.
A permanent magnet can affect:
O
A. both permanent magnets and electromagnets.
O B. both non-magnets and electromagnets.
O
c. only permanent magnets.
O
D. only electromagnets and charged particles.
SUBMIT
Answer: A
both permanent magnet and electromagnets.
i hope that helps
Final answer:
A permanent magnet can affect both other permanent magnets and electromagnets, as well as metals such as iron and nickel. It cannot attract non-metals like plastic or wood and can also exert a force on charged particles when they are in motion.
Explanation:
The question concerns the effects a permanent magnet can have on various objects and fields, particularly addressing what a permanent magnet can affect. A permanent magnet can affect both other permanent magnets and electromagnets by exerting a magnetic force on them. Magnets can also affect objects made of materials that are attracted to magnets, such as iron and nickel. These materials are typically metals, not non-metals like plastic or wood, which do not respond to magnetic fields.
Furthermore, a magnetic field can exert a force on charged particles, such as electrons, when they are in motion. This is a fundamental principle of electromagnetism, a branch of physics that studies the interaction between electricity and magnetism. Consequently, the correct answer to the question is that a permanent magnet can affect both permanent magnets and electromagnets.
How many joules are required for melting 12.8g of ice at 0 degrees Celsius?
Answer:
4,270 Joules
Explanation:
The heat of fusion of water is 334 j/g. So, the equation would be (12.8 g)(334 j/g) which comes to 4,270 joules.
Written out that's just twelve point eight times three hundred and thirty four.
To melt 12.8g of ice at 0 degrees Celsius, one would need 4275.2 joules of energy. This is calculated by multiplying the mass of the ice (12.8g) by the heat of fusion for ice (334 J/g).
To determine how many joules are required for melting 12.8g of ice at 0 degrees Celsius, we should use the known heat of fusion for ice. The heat of fusion of ice is 334 J/g, which is the amount of energy needed to convert 1 gram of ice at its melting point into 1 gram of water at the same temperature without changing its temperature.
The calculation is straightforward:
First, find the energy required to melt a single gram of ice which is 334 J/g.Multiply this value by the mass of the ice in grams to find the total energy required.In this case:
Energy required = 334 J/g × 12.8 g = 4275.2 J
Therefore, 4275.2 joules of energy are required to melt 12.8g of ice at 0 degrees Celsius.
What is the poH of a 0.0235 M HCl solution?
Answer:
12.371
Explanation:
pH of a 0.0235 M HCl solution is;
pH = -log[H+ ] = -log(0.0235) = 1.629
pOH = 14.000 – pH = 14.000 – 1.629 = 12.371
Taking into account the definition of pH and pOH, the pOH of a 0.0235 M HCl solution is 12.37.
In first place, pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance. Mathematically, pH is expressed as the negative base 10 logarithm of the hydrogen ion concentration:
pH= - log [H⁺]= -log [H₃O⁺]
A strong acid is an acid that ionizes almost completely in aqueous solution, so the concentration of protons equals the concentration of the acid.
Being HCl a strong acid, then
[HCl]= [H⁺]= [H₂O⁺]= 0.0235 M
Then, the pH of the solution is:
pH= -log (0.0235 M)
pH= 1.63
On the other hand, pOH is a measure of the concentration of hydroxyl ions in a solution. The following relationship can be established between pH and pOH:
pH+ pOH= 14
In this case:
1.63 + pOH= 14
Solving:
pOH= 14 - 1.63
pOH= 12.37
Finally, the pOH of a 0.0235 M HCl solution is 12.37.
Learn more about:
pH: https://brainly.com/question/3992824?referrer=searchResultspH and pOH: https://brainly.com/question/13423425?referrer=searchResultsHow does geothermal energy help form rocks?
Which of the following statements describes a problem associated with
chemicals made by chemists?
O
A. They are in medicines,
O
B. They can be released into the environment,
C. They can be found in food,
O
O
D. They can be in cleaning products.
Answer:
option a is answer
Explanation:
suppose we take an example of sodium chloride is always used in medicines
Answer:it’s b
Explanation: trust meh Brodie
Name two kinds of rocks formed by conduction of energy.
Answer:
pumice and gneiss
Explanation:
both are formed by conduction of energy
Determine the shape around the atoms in ethambutol
Answer:
The structure of Ethambutol is attached below. As it can be seen in structure that there are three different atoms which can act as a central atom and hence, can make a geometrical shape. These three atoms are;
(i) Carbon (Tetrahedral):
Each carbon atom in this compound is Sp³ hybridized because there is no double or triple bond in this compound. So, according to VSEPR theory the four bonded atoms will keep a maximum distance from each other to experience less repulsion. Therefore, the bond angle about carbon atom will be 109.5° and the shape will be Tetrahedral.
(ii) Nitrogen (Trigonal Pyramidal):
There are two atoms of Nitrogen in this compound. These Nitrogen atoms are bonded to three atoms. Also, it has one lone pair of electron. This pair of electron will cause the the bond between the atoms to decrease due to more repulsion hence making the bond angle less than 109.5° and giving a Trigonal Pyramidal shape.
(iii) Oxygen (Bent / Angular):
The two oxygen atoms are bonded to two atoms and contain two lone pair of electrons, hence, more repulsion and more small angle i.e. 104° giving a bent or angular shape.
When hydrochloric acid reacts with sodium sulfide, hydrogen sulfide gas and sodium chloride are produced. How many moles of H2S will be generated by 2.56 moles of HCl?
2HCl + Na2S → H2S + 2NaCl
Answer:
mol H2S = 1.28 mol
Explanation:
balanced reaction:
2HCl + Na2S → H2S + 2NaCl∴ moles HCl = 2.56 mol
⇒ moles H2S = ?
⇒ moles H2S = (2.56 mol HCl)*(mol H2S/2 moles HCl)
⇒ moles H2S = 1.28 mol
How many particles are there in 3 moles of Fe
Answer:
n=N/Na
----. N=nxNa=3x6.023x10^23=1.8069e+24
A box is initially at the top of a slide, storing 80 J of gravitational energy. The isolated system includes the box, slide and earth.
As the box slides down the frictionless slide, what happens to the total energy of the system?
1-the isolates system stores slightly less than 80 J of total energy, and it is converted to a different form of energy
2- The isolated system stores 80 J of total energy, but it is converted to a different foe of energy
3- The total energy of the system increases to more than 80 J as it gains other forms of energy
4- The total energy of isolated system decreases to 0 once the box reaches the bottom of the slide
Answer:
It stays àt 80j
Explanation:
The total energy of the isolated system remains 80 J as the gravitational potential energy is converted into kinetic energy in a frictionless environment, maintaining conservation of energy.
As the box slides down the frictionless slide, the total energy of the system remains constant due to the conservation of energy principle. The initial 80 J of gravitational potential energy is progressively converted into kinetic energy as the box moves down the slide. Since the slide is frictionless, there are no dissipative forces like friction to convert mechanical energy into heat. Hence, the isolated system, which includes the box, slide, and earth, will still store 80 J of total energy, but in different forms (mostly kinetic energy when the box is at the bottom of the slide).
write with examples two conditions under which a double displacement reaction can proceed.
Double displacement reaction:
A double replacement or displacement reaction, the process in which two compounds react and interchange positive cations and negative anions of two reagents, and created two new forms of compounds or products.
Conditions:
For this to occur, start with ionic compounds of two in an aqueous solutions (dissolved in [tex]\mathrm{H}_{2} \mathrm{O}[/tex]).They should react to create an insoluble precipitates, water or gas.A feature of this is that two compounds are reagents and two various compounds are products.
Production of insoluble precipitate
[tex]A g N O_{3}(a q)+N a C l(a q) \rightarrow A g C l(s)+N a N O_{3}(a q)[/tex]
Production of an insoluble gas
[tex]N a_{2} S(a q)+2 H C l(a q) \rightarrow 2 N a C l(a q)+H_{2} S(g)[/tex]
Production of water
[tex]H N O_{3}(a q)+K O H(a q) \rightarrow K N O_{3}(a q)+H_{2} O(l)[/tex]
Examples:
An example is the reaction between silver nitrate and sodium chloride. Silver converts a nitrite ion to a sodium chloride ion, and sodium absorbs a nitrate anion.
[tex]A g N O_{3}+N a C l \rightarrow A g C l+N a N O_{3}[/tex]
Also, other example as below
[tex]\mathrm{CuCl}_{2}(a q)+2 A g N O_{3}(a q) \rightarrow C u\left(N O_{3}\right)_{2}(a q)+2 A g C l(s)[/tex]
There are two equivalent ways to maintain a double displacement equation: cation exchange or anion exchange.
If 5.50 mol of HCl and 3.00 mol of O2 react according to the following equation, how many grams of water will form?
Answer:
49.52 g of H₂O
Explanation:
The balance chemical equation for given reaction is as follow;
4 HCl + O₂ → 2 H₂O + 2 Cl₂
Step 1: Find out Limiting reagent as;
According to balance equation,
4 moles of HCl reacted with = 1 mole of O₂
So,
5.50 moles of HCl will react with = X moles of O₂
Solving for X,
X = 5.50 mol × 1 mol / 4 mol
X = 1.375 moles of O₂
This means to completely consume 5.5 moles of HCl we will need 1.375 moles of O₂ while, we are provided with 3.0 moles of O₂ which is in excess hence, the limiting reagent in this problem is HCl and it will control the yield of products.
Step 2: Calculate Moles of H₂O produced;
According to balance equation,
4 moles of HCl produced = 2 moles of H₂O
So,
5.50 moles of HCl will react with = X moles of H₂O
Solving for X,
X = 5.50 mol × 2 mol / 4 mol
X = 2.75 moles of H₂O
Step 3: Calculate Mass of H₂O as;
Mass = Moles × M.Mass
Mass = 2.75 mol × 18.01 g/mol
Mass = 49.52 g of H₂O
what is the chemical symbol for lead
Answer:
Lead (/ˈlɛd/) is a chemical element with the symbol Pb
an advertisement for a commercial hand warmer claims that the hand warmer works because a chemical reaction in the hand warmer draws out the body’s own natural heat causing a warming effect
"An advertisement for a commercial hand warmer claims that the hand warmer works because a chemical reaction in the hand warmer draws out the body’s own natural heat causing a warming effect"
Explanation:
Hand warmer
Hand warmers are the pockets which produce heat, that you hold on the hands to warm your fingers. Niichi Matoba, the Japanese inventor created the first commercially manufactured hand warmer. Two types of hand warmersA) Crystalline type
B) Air activated
C) Lighter
D) Battery
E) Charcoal
The chemicals produce heat from oxidizing iron into rust or iron oxide in the pockets. Each packet contains cellulose, iron, vermiculite activated carbon, water and salt. Hand warmer produces heat for 1 to 10 hrs. Releases heat in the crystallization process. Exothermic reaction to release heat in the chemical hand warmer. The hand warmer lasts only for 20 minutes to 2 hrs.it Is reusable. Supersaturated solution of sodium acetate in water is the common chemical used in this product. These temperature reach up to 163 degrees Fahrenheit.Answer:
false
Explanation:
Elements that typically give up electrons _______
Answer:
metals? I'm not 100% sure, sorry if I'm wrong.
6. {THROWBACK!!) A sample of CO2 gas has a volume of 145 Lat STP. How many grams of CO2 are in this sample?
Answer:
284.88 grams of CO₂
Explanation:
Data Given:
Volume = V = 145 L
Standard Temperature = T = 273.15 K
Standard Pressure = P = 1 atm
Universal Gas Constant = R = 0.08205 L⋅atm⋅K⁻¹⋅mol⁻¹
Moles = n = ??
Formula Used:
Assuming that the CO₂ gas is acting ideally we will apply Ideal Gas equation;
P V = n R T
Solving for n,
n = P V / R T
Putting values,
n = 1 atm × 145 L / 0.08205 L⋅atm⋅K⁻¹⋅mol⁻¹ × 273.15 K
n = 6.47 mol
Secondly, Moles are converted to Mass as;
Moles = Mass / M.Mass
Solving for Mass,
Mass = Moles × M.Mass
Mass = 6.47 mol × 44.01 g/mol
Mass = 284.88 grams of CO₂
How is human use of coal connected to water and air quality?
The human use of coal impacts air and water quality significantly. The burning of coal results in air pollution, contributing to global health and environmental issues. Additionally, processes related to coal use also contaminate local water bodies, damaging aquatic ecosystems and affecting the safety of drinking water.
Explanation:The human use of coal has significant impacts on both air and water quality. When coal is burned for energy, it releases pollutants, including sulfur dioxide and nitrogen oxides into the atmosphere. These substances can lead to air pollution, contributing to issues like acid rain, smog, respiratory diseases, and global warming.
Coal mining and combustion also affect water quality. Acid mine drainage, where water in coal mines becomes acidic and leaks out, can contaminate local water bodies, harming aquatic life and making the water unsafe for human consumption. Moreover, coal-fired power plants often discharge waste materials containing heavy metals like mercury into water bodies, further deteriorating water quality.
Learn more about the Impact of coal on air and water quality here:https://brainly.com/question/32849086
#SPJ2
Calculate the mass of 15.73 L of krypton gas at STP.
Answer: m= 58.8 g Kr
Explanation: solution attached:
Find first the number of moles for Kr.
Use Ideal gas law formula PV= nRT and derive for n.
Convert moles to mass using the molar mass of Kr.
How many atoms are contained in 0.633 moles of Ni? ( show work)
Answer:
1.0511458x10^22
Explanation:
0.633 mol/ 1 x 6.022x10^23/1 mol
Given this equation: 3 MgCl2 + 2 AL - 3 Mg + 2 AlCl3, if 278 grams of magnesium chloride
reacted how many grams of aluminum chloride are produced?
O mass to mass
moles to mass
mass to moles
moles to moles
D
Question 3
5 pts
Answer: m= 1.02x10² g AlCl3 or 1091.3 g AlCl3
Explanation: solution attached.
Convert mass of Mg to moles
Do the mole ratio between Mg and AlCl3 based from the balanced equation.
Convert moles of AlCl3 to mass using its molar mass.
Which are made of matter?
living things only
both living and nonliving things
nonliving things only
some living and all nonliving things
Yo sup??
The correct answer is option B ie
both living and non living things.
Hope this helps
The correct answer is that both living and nonliving things are made of matter. The correct option is: both living and nonliving things.
Living organisms and inanimate objects alike are composed of matter. Essentially, matter is the "stuff" that constitutes everything in existence. Anything that occupies space and has mass qualifies as matter, which consists of various chemical substances.
Therefore, the accurate answer to the question "What is made of matter?" encompasses both living and nonliving entities. This includes everything from the air we breathe to the earth beneath our feet, the food we consume, and our own bodies.
For example, the chair you're sitting on and the meal you had for lunch are both made of matter. Matter, defined as anything that has mass and takes up space, includes all tangible objects in the universe, whether living or nonliving.
How many orbitals are in the n = 3 level?