Answer:
57.48%
Explanation:
Calculate the mass of 1 mole of malachite:
MM Cu = 63.55
MM O = 16.00
MM H = 1.01
MM C = 12.01

A mole of malachite has:
2 moles of Cu
5 moles of O
2 moles of H
1 mole of C
MW Malachite = 2*MM(CU) + 5*MM(O) + 2*MM(H) + 1 *MM(C)
MW Malachite = 2*63.55 + 5*16.00 + 2*1.01 + 1*12.01
MW Malachite = 221.13
Mass of Cu in a mole of Malachite = 2*MM(CU) = 127.1
Now divide the mass of Cu by the mass of Malachite

Answer: formic acid (HCOOH) contains the greatest mass of oxygen
Explanation:Please see attachment for explanation
Answer:
B. Excited state
Explanation:
Energy levels higher than the ground state are called the excited states. This concept is based on the premise that electrons can move round the nucleus in certain permissibe orbits or energy levels.
The ground state is the lowest energy state available to the electron. This is usually the most stable state.
The excited state is any level higher than the ground state. An electron in an energy level has a definite amount of energy associated with it at that level.