A sample of mercury is heated from 25.5 °C to 52.5 °C. In the process, 3050J of heat

are absorbed. What mass of mercury was in the sample? The specific heat of mercury is 140 J/g °C.

Calculate ∆h0 for the following reaction. br2 ( g. → br2 (l) ∆hf0 br2 ( g. = 30.91 kj/mol; ∆hf0 br2 (l) = 0 kj/mol)

How are chemical and physical changes different on a molecular level? Chemical changes involve the breaking of bonds in molecules. Physical changes do not involve molecules. Physical changes cause new molecules to form.

if the charcoal from an ancient fire contains 1/512 amount of carbon-14 as a living tree, how long ago did the fire occur? the half life of carbon-14 is 5730 years

9. In a sample of gas, what causes pressure? Answer in a completesentence.

Five liters of gas at STP have a mass of 12.5 g. What is the molecular mass of the gas? a. 12.5 g/mol b. 25.0 g/mol c. 47.5 g/mol d. 56.0 g/mol e. 125 g/mol

If 35.50 cm3 of a NaOH solution are required for the complete neutralization of a 25.00cm3 sample of 0.200mol dm-3 H2SO4, what is the concentration of the NaOH solution?

Explain the difference between the literal, supernatural, and psychological levels in a story

List the four (4) ways you can tell that a chemical reaction has occurred.

The Ka of a monoprotic weak acid is 6.07 * 10-3. What is the percent ionization of a 0.179 M solution of this acid?

What does LeChatelier's principal mean