Which temperature change indicates an increase in the average kinetic energy of the molecules in a sample? 15°C to 298 K 37°C to 273 K 305 K to 0°C 355 K to 25°C

The oxide of element X is reduced by heating with carbon. Element X does not react with cold water, steam or dilute hydrochloric acid. What is X?

What is the mass of a neutron?

Which of the following statements regarding resonance structures is true? 1) They differ only in their arrangement of electrons. 2) The true structure is a hybrid of possible resonance structures.

How many moles of chlorine gas would occupy a volume of 35.5 L at a pressure of 0.98 atm and a temperature of 373 K?

Explain how you think scientists know (think they know) about the inner Earth?

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?