q= mC(delta T)

(100g) x 4.17(J/gxC) x (57-22C) = 14600 J

You can find this equation on Table T.  You can find the value for specific heat capacity on Table B.

14%

30.2-25.9 = 4.3

4.3/30.2 = 14%

When the candle is burned, energy is released in the form of light and heat.

When energy is released, a chemical change has taken place.

melting

The wax changes from solid to liquid so it melts.

Solidification also occurs as the melted wax cools and hardens.

(1) Hydrogen gas burns in air is the correct answer.

Chemical properties describe an element’s ability to undergo change.  Answers 2, 3, and 4 describe physical properties of hydrogen.  Only answer 1 describes a chemical change, the combustion of hydrogen.

(4) low temperature and high pressure is the correct answer.

Unlike solids in liquid, where solubility increases with temperature, the solubility of a gas in liquid increases with a lower temperature.

Henry's law is used to measure the solubility of gases in solvents. The solubility of a gas in a solvent is directly proportional to the partial pressure of that gas above the solvent. This relationship is written as:

p = kc

where k is a temperature-dependent p is the partial pressure (atm), and c is the concentration of the dissolved gas in the liquid (mol/L).  As the pressure increases, the solubility increases.

Therefore, gases are most soluble in water at a low temperature and a high pressure.

(3) Heat of reaction is the correct answer.

Heat of reaction is the amount of energy that must be added or removed during a reaction to keep the products and reactants at the same temperature which can also be defined as the difference in energy of the products and the reactants.

4) transmutation is the correct answer.

Transmutation is a nuclear process which converts one chemical element into another.

Combustion is the reaction that occurs when a compound is burned.

Saponification is the process used to make soap.

Polymerization is the process of joining many small molecules to form a larger molecule.

(2) A and C is the correct answer.

The equation PV=nRT lets us know that ideal gas samples with the same temperature, pressure, and volume, will contain the same number of gas molecules.  In this case, samples A and C meet this standard.

(2) 60 C is the correct answer.

You can refer to Table H and compare the curves of ethanol and propanone.  If you find the vapor pressure of propanone at 35C (about 50 kPa), you can see that ethanol reaches this vapor pressure at 60 C.