Which of the following are examples of pure substances? (choose more than one)
a. silver
b. water
c. air
d. carbon dioxide
e. saltwater
a. silver (Ag)
b. water (H2O)
d. carbon dioxide (CO2)
***A pure substance is any element or compound, and a specific chemical formula can be written for it.***
What is the equation for determining density of an object?
density = mass / volume
What is the law of conservation of mass?
Energy cannot be created nor destroyed, it can only be changed.
What SI units are used to express specific heat capacity?
J / g * C
Joules / grams * degrees Cesius
Anything that has mass and volume.
Matter
A property that depends on the amount of matter
intensive property
32 degrees F
0 degrees C
273 K
Gold has a specific heat capacity of 0.128 J/g*C.
If a 14.3 g sample of unknown material rises in temperature from 25 to 52 C with the addition of 174 J of heat, what is its specific heat capacity, AND is it pure gold?
0.45 J/g*C.
No, it is not pure gold.
Water in a chlorinated pool is considered which classification of matter?
a. element
b. compound
c. homogeneous mixture
d. heterogeneous mixture
c. homogeneous mixture
A property that does not depend on the amount of matter
intensive property
It is equal to 0 Kelvin, the temperature at which all atomic motion ceases!
What is the temperature change in 355 mL of water upon absorbing 34 kJ of heat?
23 degrees Celsius temperature change
What is the SI base unit for mass?
kilogram (kg)
A chemical change can be represented by a balanced ______________ ________________.
A chemical change can be represented by a balanced chemical equation.
During which type of reaction is energy released from the reaction as heat?
exothermic
Provide the 2 words that complete this statement:
_________ is a measure of the average kinetic energy of the particles in a material, and
_________ is the thermal energy that is transferred from a warmer to a cooler object.
Heat
Convert 62 degrees Celsius to Fahrenheit.
144 F.
What type of change occurs when ice melts into liquid water?
Physical change
List an example of a heterogeneous mixture.
? ? ? ? ? All sorts of things! ? ? ? ?
Which statement is correct about the difference between liquids and gases of the same substance?
a. Both liquids and gases can be compressed into a smaller volume.
b. Liquids can be compressed, but gases cannot be compressed into a smaller volume.
c. Liquids cannot be compressed, but gases can be compressed into a smaller volume.
d. Neither liquids or gases can be compressed into a smaller volume.
c. Liquids cannot be compressed, but gases can be compressed into a smaller volume.
Convert 225 Joules to Calories.
5.38 x 10-2 Calories
The temperature of a lead (Pb) fishing weight rises from 26 C to 38 C as it absorbs 11.3 J of heat. What is the mass of the fishing weight in grams?
(specific heat capacity of lead: 0.128 J/g*C)
7.36 grams Pb