Review for 3rd Quarter Benchmark
Solids, Liquids and Gases
- Which of the states of matter has the largest intermolecular forces?solids
- Which of the states of matter has the weakest intermolecular forces?gases
- What is the key characteristic that distinguishes a solid from a liquid?shape
- Which of the following states of matter has particles that can only vibrate in place?
- Solid
- Liquid
- Gas
- Which of the following states of matter has particles that are not bonded and can randomly move around to fill the volume of their container?
- Solid
- Liquid
- Gas
- Which of the following states of matter has particles that slide past one another in random patterns?
- Solid
- Liquid
- Gas
- What are the values for the temperature and pressure at STP?
Pressure=1atm or 760mmHg
Temperature=0oC or 273Kelvin
- What volume does one mole occupy at STP?22.4L
- What is absolute zero?-273oCand 0 K
- What happens at absolute zero?all motion stops
- Can you have a temperature below absolute zero?no
- Convert the following temperatures from Celsius to Kelvin.
a.225oC498 K
b.300oC573 K
c.-270oC3 K
- Convert the following temperatures from Kelvin to Celsius.
a.95 K-178oC
b.273 K0oC
c.1550 K1277oC
- If you open a sealed container of gas and the gas spreads out to fill the volume of the room, this process is called?
- Gas pressure
- Depression
- Diffusion
- Kinetic energy
True or false
- Diffusion is the going from level of high concentration to a level of lower concentration. true
- Gas pressure is determined when gas molecules collide with the walls of a container. true
Gas Laws
- Charles law says that V1/T1 = V2/T2 so what happens to the temperature if the volume increases? increase
- Charles law says that V1/T1 = V2/T2 so what happens to the temperature if the volume decreases? decrease
- Gay-Lussac’s law says that P1/T1 = P2/T2 so what happens to the temperature if the pressure increases? increase
- Gay-Lussac’s law says that P1/T1 = P2/T2 so what happens to the temperature if the pressure decreases? decrease
- Boyles’s law says that P1V1 = P2V2 so what happens to the volume if the pressure increases? decrease
- Boyles’s law says that P1V1 = P2V2 so what happens to the volume if the pressure decreases? increase
- A gas at 45K and a pressure of 0.333 atm is heated to 800K. Predict whether the pressure will increase or decrease? What will the new pressure be?
.333atm(800K) = 5.92
45K
- A container filled with 60L of gas at 2000K is cooled to 500K. Predict whether the volume will increase or decrease? What will the new volume be?
60L(500K) = 15L
2000K
- A gas at 250 L and a pressure of 6 atm is heated to 900 L. Predict whether the pressure will increase or decrease? What will the new pressure be?
250L(6atm) = 1.667atm
900L
Solutions
- What is a solute?Gets dissolved
- What is a solvent? Substance a solute is dissolved in
- What is a solution?the mixture
- If salt is dissolved in water, what is the solvent and what is the solute? Salt salute, water solvent
True or false
- When salt dissolves in water the salt crystal separates into ions.true
- Stirring increases the rate of dissolving?true
Solutions
- What is the molarity of a solution made with 30 g of NaOH dissolved in 2.5 L of water?
30g x 1mole = 0.75moles
40g
0.75moles = 0.3M
2.5L
- If you made 3 L of a 5 M solution of NaCl how much NaCl did you need to use?
3L x 5mole = 15moles
L
Thermochemistry
- What happens to the temperature in an endothermic reaction?
It gets colder
- What happens to the temperature in an exothermic reaction?
It heats up
- If a reaction gives off heat is it endothermic or exothermic?
exothermic
- If a reaction absorbs heat is it endothermic or exothermic?
endothermic
What do we call the following changes of state (melting, freezing…) and are they endothermic or exothermic.
Phase change Endo/Exothermic
- Converting from a solid to a liquid.Melting endothermic
- Converting from a liquid to a solid.Freezing exothermic
- Converting from a liquid to a gas.boiling endothermic
- Converting from a gas to a liquid.Condensationexothermic
- Converting from a solid to a gas.Sublimationendothermic
- Converting from a gas to a solid.depositionexothermic
- How much heat will be released when 4.72 g of carbon reacts with excess O2 according to the fallowing equation?
C + O2 CO2∆H°= -393.5 kJ/moles
4.72g x 1mole = 0.3933mole
12g
0.3933mole x -393.5kJ = -154.77kJ
mole
- How much heat will be absorbed when 38.2 g of bromine reacts with excess H2 according to the fallowing equation?
H2 + Br2 2HBr∆H°= -72.80 kJ/moles
38.2g x 1moleBr = 0.239 mole
159.8g
0.239mole x -72.80kJ = -17.4 kJ
mole
- For the following energy diagrams label products, reactants, the activation energy and if it is an exothermic or endothermic reaction.