1. How Is Molar Mass Calculated And Why Is It Useful?
Moles
1.How is molar mass calculated and why is it useful?
You have to multiply the atomic weight of each element by the number of atoms that it contains in a compound. Molar mass is useful because its used to change a measurement of mass to an amount of a substance such as the number of particles.
2.Define a mole in chemistry and give 3 examples equivalent units that are used in chemical calculations.
A mole measures the amount of a substance. Three examples that are equivalent to a mole is molar mass, 22.4L, 6.02x10^23 (avogadro’s number).
Gas Laws
3.How is the combined gas law used to calculate differences in pressure, temperature and/or volume for a fixed amount of gas?
The combined gas law is P1V1/T1=P2V2/T2 and this equation is used to find the difference …show more content…
in pressure, temperature and volume for a fixed amount of gas by simply eliminating the variable that is represented in the law by a kind of algebraic action. For instance when trying to find the fixed amount for Temperature and in the problem you’re given the pressure then you would eliminate the V from the equation then you would use the information given for pressure and temperature (make sure to convert Celsius to Kelvin) then you would get your amount.
4.What is the ideal gas law and what does R represent?
The ideal gas law is PV=nRT and R represents the ideal gas constant of 0.0821 L* atm/K*mol.
Solutions
5.What factors affect the rate at which a solution dissolves?
Factors such as the temperature, how much solution or substance there is, shaking or stirring the solution, and decreasing the size of substance particles affects the rate at which a solution dissolves.
6.What are the various parts of a solution?
The various parts of a solution consists of solutes and solvents. The solute is part of the solution that gets dissolved in the solvent such as in a solution of sugar water, the sugar would be the solute. The solvent is what the solute is put into in order to dissolve such as the water in the solution of sugar water.
7.Distinguish between an unsaturated, saturated, and supersaturated solution.
Unsaturated solution is when all the solute in a solution have been dissolved in the solvent, and the solvent could’ve dissolved even more solute that was present. Saturated solutions are when the solvent dissolves the maximum amount of solute it can handle. Supersaturated solutions are solutions where there was more solute present than what the solvent could dissolve under regular conditions without any added heat.
Acids and Bases
8.What occurs during a neutralization reaction (process)?
When a base and acid creates a reaction forming water and a salt.
9.How does the pH scale and the concentration of a solution related?
The higher the pH level, the lower the concentration level will be of a substance therefore the pH scale and concentration of a solution will have an inverse relationship.
10.Describe the differences in Acids and Bases?
Acids are substances that have a pH lower than 7 on the pH scale, and they donate their hydrogens. Bases are solutions that have a pH higher than 7 on the pH scale, and they accept hydrogen ions.
11.What are the differences in the Arrhenius Theory and the Bronsted-Lowry Theory?
The Arrhenius Theory states that acids in a solution produces hydrogen ions and bases make hydroxide ions in a solution. The Bronsted-Lowry Theory says that an acid is a hydrogen ion (proton) donor while a base is a hydrogen ion (proton) acceptor. Arrhenius Theory thought that hydroxide ions were always in a base, and when it dissolves in water, the hydroxide ions would be released. But the Bronsted-Lowry Theory stated that a base accepts a proton to a molecule, so it’s similar to being the reversed to an
acid.
Thermochemistry
12.What is specific heat? What factors are needed to calculate the specific heat of a substance? Why do different materials have different specific heat values?
Specific heat is the amount of heat needed to increase a unit of mass of a body’s temperature. Factors such as the amount of heat added, the mass, and the change in temperature are needed to calculate specific heat. Different materials have different specific heats because substances have different molecular structures, strengths, and densities which will lead to different amounts of energy to heat them up.
13.How do you distinguish between endothermic and exothermic reactions and processes?
Endothermic reactions and processes absorb heat which causes the reactions surroundings to be cool, but since exothermic reactions and processes release heat, this causes the surrounding to be hotter which is opposite of endothermic.
14.What does Hess’ Law allow you to do? How do you calculate a change in enthalpy?
Hess’ Law allows you to find out the change of enthalpy by calculating it when it's too difficult to be measured. You calculate enthalpy by using the equation q=mxcx∆T where q is enthalpy, m is mass, c is specific heat capacity of water, and ∆T is the change in temperature.
Nuclear
15.How do fission and fusion compare and contrast? (used nuclear powerpoint on moodle)
Nuclear fission provides nuclear power plant’s energy and fusion is the source of the sun’s energy. Fission has a heavy nucleus that is split into two or more stable nuclei. Fusion is when a heavy and stable nuclei is formed when low mass nuclei combine.
16.How do alpha, beta, and gamma radiation compare and contrast? (used nuclear powerpoint on moodle)
Alpha radiation involves two neutrons and two protons with a large mass, a +2 positive charge, with low penetrating power. Beta radiation involves an electron being emitted from the nucleus, with no mass, a -1 charge, and a higher penetrating power. Gamma radiation involves high energy EM waves with no mass or charge, and it has the highest penetrating power.
17.What subatomic particles are involved in the transformation of the nucleus during radioactive decay?
During radioactive decay if the nucleus, the neutrons and protons that are in the nucleus split, which also shows how when there’s an unstable nuclei, beta particles are released.
18.Where do isotopes come from?
Isotopes come from having a different amount of neutrons as an atom.
EM
19.Identify the parts of a wave
There’s crest which is the top of one of the waves on the spectrum with the maximum value, trough is the bottom part of the waves on the spectrum with minimum value, and amplitude is the distance of the wave from zero. The wavelength is the space between two identical points of waves.
20.Describe the components EM spectrum from longest to shortest wavelength, include the name, description, use, and frequency. (for this question I used the chart we did in class)
The components of the EM spectrum from longest to shortest wavelength is radio waves, microwaves, infrared waves, visual waves, ultraviolet waves, x-ray waves, and gamma waves. Radio waves are used in transmitting television signals, they are the longest wavelength, and their wavelengths can easily travel through the atmosphere to the earth’s surface with the lowest frequency. Microwaves are used in cellphones and radars as well as used to quickly cook and heat foods. Their wavelengths are shorter than radio waves, but longer than infrared, and their frequency is higher than radio waves, but lower than infrared. Infrared waves are used to heat lamps and is sometimes used in detecting location of newborn stars. Their wavelengths are shorter than microwaves, but longer than visible light, and their frequency is higher than microwaves, but lower than visible light. Visible light are used as the only part of the spectrum we can see. They consists of wavelengths of red, orange, yellow, green, blue, and violet (ROYGBIV) which are shorter than infrared yet longer than ultraviolet, and they have a higher frequency than infrared, but a lower frequency than ultraviolet. Ultraviolet is used to help produce vitamin D, but it can cause sunburns, and it carries more energy than visible light but less than x-ray, and has a shorter wavelength than visible light, but a longer one than x-ray. X-rays are used to treat cancer cells and sometimes used to detect black holes. They have more energy than UV rays but less than gamma rays. Their frequency is higher than ultraviolet, but less than gamma rays, and their wavelength is longer than gamma rays, but shorter than ultraviolet. Gamma rays are useful for medical applications and they are sometimes used to detect black holes. These waves have the greatest amount of energy and smallest wavelength out of all of the waves.
21.How does frequency, wavelength, and velocity relate?
Any electromagnetic wave's wavelength multiplied by its frequency equals the velocity of light, therefore frequency, wavelength, and velocity are related through this equation.
1.How is molar mass calculated and why is it useful?
You have to multiply the atomic weight of each element by the number of atoms that it contains in a compound. Molar mass is useful because its used to change a measurement of mass to an amount of a substance such as the number of particles.
2.Define a mole in chemistry and give 3 examples equivalent units that are used in chemical calculations.
A mole measures the amount of a substance. Three examples that are equivalent to a mole is molar mass, 22.4L, 6.02x10^23 (avogadro’s number).
Gas Laws
3.How is the combined gas law used to calculate differences in pressure, temperature and/or volume for a fixed amount of gas?
The combined gas law is P1V1/T1=P2V2/T2 and this equation is used to find the difference …show more content…
in pressure, temperature and volume for a fixed amount of gas by simply eliminating the variable that is represented in the law by a kind of algebraic action. For instance when trying to find the fixed amount for Temperature and in the problem you’re given the pressure then you would eliminate the V from the equation then you would use the information given for pressure and temperature (make sure to convert Celsius to Kelvin) then you would get your amount.
4.What is the ideal gas law and what does R represent?
The ideal gas law is PV=nRT and R represents the ideal gas constant of 0.0821 L* atm/K*mol.
Solutions
5.What factors affect the rate at which a solution dissolves?
Factors such as the temperature, how much solution or substance there is, shaking or stirring the solution, and decreasing the size of substance particles affects the rate at which a solution dissolves.
6.What are the various parts of a solution?
The various parts of a solution consists of solutes and solvents. The solute is part of the solution that gets dissolved in the solvent such as in a solution of sugar water, the sugar would be the solute. The solvent is what the solute is put into in order to dissolve such as the water in the solution of sugar water.
7.Distinguish between an unsaturated, saturated, and supersaturated solution.
Unsaturated solution is when all the solute in a solution have been dissolved in the solvent, and the solvent could’ve dissolved even more solute that was present. Saturated solutions are when the solvent dissolves the maximum amount of solute it can handle. Supersaturated solutions are solutions where there was more solute present than what the solvent could dissolve under regular conditions without any added heat.
Acids and Bases
8.What occurs during a neutralization reaction (process)?
When a base and acid creates a reaction forming water and a salt.
9.How does the pH scale and the concentration of a solution related?
The higher the pH level, the lower the concentration level will be of a substance therefore the pH scale and concentration of a solution will have an inverse relationship.
10.Describe the differences in Acids and Bases?
Acids are substances that have a pH lower than 7 on the pH scale, and they donate their hydrogens. Bases are solutions that have a pH higher than 7 on the pH scale, and they accept hydrogen ions.
11.What are the differences in the Arrhenius Theory and the Bronsted-Lowry Theory?
The Arrhenius Theory states that acids in a solution produces hydrogen ions and bases make hydroxide ions in a solution. The Bronsted-Lowry Theory says that an acid is a hydrogen ion (proton) donor while a base is a hydrogen ion (proton) acceptor. Arrhenius Theory thought that hydroxide ions were always in a base, and when it dissolves in water, the hydroxide ions would be released. But the Bronsted-Lowry Theory stated that a base accepts a proton to a molecule, so it’s similar to being the reversed to an
acid.
Thermochemistry
12.What is specific heat? What factors are needed to calculate the specific heat of a substance? Why do different materials have different specific heat values?
Specific heat is the amount of heat needed to increase a unit of mass of a body’s temperature. Factors such as the amount of heat added, the mass, and the change in temperature are needed to calculate specific heat. Different materials have different specific heats because substances have different molecular structures, strengths, and densities which will lead to different amounts of energy to heat them up.
13.How do you distinguish between endothermic and exothermic reactions and processes?
Endothermic reactions and processes absorb heat which causes the reactions surroundings to be cool, but since exothermic reactions and processes release heat, this causes the surrounding to be hotter which is opposite of endothermic.
14.What does Hess’ Law allow you to do? How do you calculate a change in enthalpy?
Hess’ Law allows you to find out the change of enthalpy by calculating it when it's too difficult to be measured. You calculate enthalpy by using the equation q=mxcx∆T where q is enthalpy, m is mass, c is specific heat capacity of water, and ∆T is the change in temperature.
Nuclear
15.How do fission and fusion compare and contrast? (used nuclear powerpoint on moodle)
Nuclear fission provides nuclear power plant’s energy and fusion is the source of the sun’s energy. Fission has a heavy nucleus that is split into two or more stable nuclei. Fusion is when a heavy and stable nuclei is formed when low mass nuclei combine.
16.How do alpha, beta, and gamma radiation compare and contrast? (used nuclear powerpoint on moodle)
Alpha radiation involves two neutrons and two protons with a large mass, a +2 positive charge, with low penetrating power. Beta radiation involves an electron being emitted from the nucleus, with no mass, a -1 charge, and a higher penetrating power. Gamma radiation involves high energy EM waves with no mass or charge, and it has the highest penetrating power.
17.What subatomic particles are involved in the transformation of the nucleus during radioactive decay?
During radioactive decay if the nucleus, the neutrons and protons that are in the nucleus split, which also shows how when there’s an unstable nuclei, beta particles are released.
18.Where do isotopes come from?
Isotopes come from having a different amount of neutrons as an atom.
EM
19.Identify the parts of a wave
There’s crest which is the top of one of the waves on the spectrum with the maximum value, trough is the bottom part of the waves on the spectrum with minimum value, and amplitude is the distance of the wave from zero. The wavelength is the space between two identical points of waves.
20.Describe the components EM spectrum from longest to shortest wavelength, include the name, description, use, and frequency. (for this question I used the chart we did in class)
The components of the EM spectrum from longest to shortest wavelength is radio waves, microwaves, infrared waves, visual waves, ultraviolet waves, x-ray waves, and gamma waves. Radio waves are used in transmitting television signals, they are the longest wavelength, and their wavelengths can easily travel through the atmosphere to the earth’s surface with the lowest frequency. Microwaves are used in cellphones and radars as well as used to quickly cook and heat foods. Their wavelengths are shorter than radio waves, but longer than infrared, and their frequency is higher than radio waves, but lower than infrared. Infrared waves are used to heat lamps and is sometimes used in detecting location of newborn stars. Their wavelengths are shorter than microwaves, but longer than visible light, and their frequency is higher than microwaves, but lower than visible light. Visible light are used as the only part of the spectrum we can see. They consists of wavelengths of red, orange, yellow, green, blue, and violet (ROYGBIV) which are shorter than infrared yet longer than ultraviolet, and they have a higher frequency than infrared, but a lower frequency than ultraviolet. Ultraviolet is used to help produce vitamin D, but it can cause sunburns, and it carries more energy than visible light but less than x-ray, and has a shorter wavelength than visible light, but a longer one than x-ray. X-rays are used to treat cancer cells and sometimes used to detect black holes. They have more energy than UV rays but less than gamma rays. Their frequency is higher than ultraviolet, but less than gamma rays, and their wavelength is longer than gamma rays, but shorter than ultraviolet. Gamma rays are useful for medical applications and they are sometimes used to detect black holes. These waves have the greatest amount of energy and smallest wavelength out of all of the waves.
21.How does frequency, wavelength, and velocity relate?
Any electromagnetic wave's wavelength multiplied by its frequency equals the velocity of light, therefore frequency, wavelength, and velocity are related through this equation.