What is the second most abundant element in stars?

A.

iron

B.

helium

C.

oxygen

D.

hydrogen

How many moles of h2so4 are needed to neutralize 1.56 moles of koh?

What two molecules were condensed in an aldol condensation to produce (ch3) 3cch=chcoch3?

Calculate the hydroxide ion concentration [OH-] for a solution with a pH of 6.10

Calculate the volume of liquid in the round flask sketched below. give your answer in liters, and round to the nearest 0.01l.

Ammonia and oxygen react to form nitrogen monoxide and water. Construct your own balanced equation to determine the amount of NO and H 2 O that would form when 2.19 mol N H 3 and 4.93 mol O 2 react.

The activation energy for the reaction no2 (g) + co (g) ⟶no (g) + co2 (g) is ea = 100 kj/mol and the change in enthalpy for the reaction is δh = - 375 kj/mol.

What process transform solar energy into chemical energy?

When the reaction was carried out the calculated theoretical yield for water was 176 grams but the measured yield was 148 grams what is the percent yield

For an atom's electrons, how many energy sublevels are present in the principal energy level n = 4?

Attempt 2 A sample of gas contains 49.16 % N 2 gas, 19.85 % Br 2 gas, 9.95 % CO 2 gas, and 21.04 % of an unknown gas. The average atomic mass of the gas mixture is 50.71 u. Calculate the atomic mass of the unknown gas.