Which of these is an example of a physical change?

A) sugar dissolving in warm water

B) iron rusting in the presence of moist air

C) wood burning in the prescence of oxygen

D) baking soda reacting with acid to form a gas

What is the mole ratio of fe304 to fe?

An individual has calculated her ecological footprint. What does this calculation tell her? O A. The area of the soles of her shoes B. The amount of land in her environment O c. The impact she has on the environment D.

Calculate the number of molecules in 9.00 moles H2S.

Convert 72g of O2 to moles

What causes the transfer of energy from one object to another? A. Differences in pressure B. Differences in temperature C. Low albedos D. High albedos

What is the relative charge carried by an electron

Which term best describes the type of bonding in magnesium chloride

This equation indicates that the reaction gives off heat. What is this type of reaction called? 2C4H10 + ? O2? 8CO2 + 10H2O + heat a. an exothermic reaction b. an endothermic reaction c. absorption reaction d. precipitation reaction

Given the balanced equation representing a reaction: C3H8 (g) + 5O2 (g) = = >3CO2 (g) + 4H2O (g) What is the total number of moles of O2 (g) required for the complete combustion of 1.5 moles of C3H8 (g) ? (1) 0.30 mol (3) 4.5 mol (2) 1.5 mol (4) 7.

What increases in equal steps of one from left to right in the Periodic Table for the elements lithium to neon?