Which equation is correctly balanced?

A) H2 + O2 H2O

B) Ca + Cl2 CaCl

C) 2 H2 + O2 2 H2O

D) Ca + Cl2 Ca2Cl

Which statement is true about a polyatomic ion?

If the original solution contained 0.12 mol hcl, what amount of hcl, in moles, will remain when the reaction is complete? 1.4 g zn reacted.

The ratio of sizes between the ionic radii of anions and cations in a cell has no influence on the manner of packing for that cell. a. True b. False

5.00 g of carbon were adiabatically burned to CO2 in a 2.00 kg copper calorimeter which contained 2.50 kg of water. The temperature increased by 14.1 °C. Specific heats: copper, 0.385 J K⁻¹ g⁻¹; water, 4.184 J K⁻¹ g⁻¹.

What is ion, electrons, neutrons?

A change in the properties of matter where chemical bonds are broken and new bonds are formed is a.) a chemical change b.) a physical change c.) an ionic change d.) a covalent change

Write a chemical equation for the chemical reaction in which calcium carbonate (CaCO3) produces calcium oxide (Cao) and carbon dioxide (CO2).

How do you know the difference between a compound and mixture?

A 68.4-g sample of potassium chloride was added to 200.0g of water at 20 degrees C. Is the solution saturated, unsaturated, or supersaturated?

If concentrated sulfuric acid is spilled during the experiment, what is the proper procedure for cleaning the spill?