Why is the earth considered a system

14.7 grams of magnesium reacts completely with 9.7 grams of oxygen to form magnesium oxide (MgO). What is the percent composition of the magnesium oxide?

For taking sip of hot tea, we blow air on it. Justify

Several substances are labeled on the pH scale below. A p H scale is shown ranging from 0 the top to 14 at the bottom. The approximate locations of substances are: gastric fluid, 1.2; lemon juice, 2.2; milk, 6.5; blood, 7.

Identify all correct statements about the ionization of water. check all that apply. check all that apply. water ionizes to form peroxide and hydronium ions. dissociation of water produces equal numbers of oh - and h+.

What are five kinds of evidence you can use to determine if a chemical reaction has occurred?

What do nucleus act as

Change of state may occur when?

During the combustion of 2.00 g of coal, the temperature of 500 g of water inside the calorimeter increased from 25.0°c to 43.7°c. the specific heat of water is 4.18 j/g·°c. how much heat did the reaction generate?

Catalysts are substances that increase the rate of reaction but can be recovered unchanged at the end of the reaction. Catalysts can be classified as either homogeneous (same state as reactants) or heterogeneous (different state than reactants).

How many molecules are there in 79g of Fe2O3?