A student boils 9.43 grams of an unknown substance into vapor. If completely vaporizing the substance required 8,720 joules of energy, what is the heat of vaporization?

3.2 moles of water is how many grams? A) 56 b) 58 c) 52 d) 54

Use the following equation to determine the charge on iron when it dissociates from oxygen and determine whether it is being oxidized or reduced: Fe2O3 + 3CO - > 2Fe + 3CO2 A. It starts with a charge of + 3 and is reduced. B.

The atomic mass of carbon-13 is 13. It has six protons. How many neutrons does this isotope have?

At the start of a measurement, a radioisotope has 10,000 unstable nuclei. over 2 days 5,000 of these unstable nuclei undergo radioactive decay to stable nuclei. what is the half life of this radioisotope?

2. What happens to the pH when you add more H + ions to a solution that has no buffers?

What are the basic building blocks of matter? A) molecules B) atoms C) electrons D) compounds

How does an atom with too few neutrons relative to protons undergo radioactive decay? * by converting proton to a neutron by converting a neutron to a proton by emitting an alpha particle

What is the chemical formula for the compound formed between sodium and iodine?

8. Write a balanced chemical equation showing how you could prepare each of the following salts from an acid-base reaction: KNO3, NaBr, and Cas.

Is calcium carbonate a compound element or mixture?