How many atoms does an element make up

How do you calculate percentage yield? What is the definition of percentage yield?

Select the correct numerical form of this number written in scientific notation. 6.2 * 10^5

What is the total number of atoms in 1.0 mole of CO2? A. 1.5 x 10^23 B. 12x 10^23 C. 3.0 x 10^23 D. 18 x 10^23

When you reacted the zinc with the hydrochloric acid, you collected the hydrogen gas by water displacement.

3 Which particle has no charge? (1) electron (3) positron (2) neutron (4) proton

The heat of combustion of propane, C3H8, is 2220 kJ/mol. The specific heat of copper is 0.385 J/g°C. How many grams of propane must be burned to raise the temperature of a 10.0 kg block of copper from 25.0°C to 65.

Which is an example of Temporal Isolation? A. Flowers that bloom in different months. B. Birds that have different mating calls C. Fruits flies that mate in different locations. D. Squirrels that have different fur colors

A chemical reaction can start when enough activation energy is added to the reactants. Do you think the activation energy for chemical reactions in living things is high or low / Explain your answer

20 Which statement describes a reversible reaction at equilibrium? (1) The activation energy of the forward reaction must equal the activation energy of the reverse reaction.

Count the total number of atoms in CaCO3: 2 3 4 5 6