Calcium has three different isotopes. One has a mass of 35 amu; another has a mass of 41 amu; and another has a mass of 40 amu. Calculate the average atomic mass of calcium.

Which of the following best describes an empirical formula? A) a chemical formula that lists the percent composition of each element B) a chemical formula that identifies the oxidation state of each element C) a chemical formula that shows the

How many molecules are in 3.0 moles of Carbon Dioxide (CO2) ? a. 1.8 X 10 24 c. 2.0 X 1024 b. 2.4 x 1023 d. 2.6 X 1024

The chemical formula for a covalently bonded group of atoms is called a

Which of the following statements incorrectly depicts the scientific method? A. Hypotheses are tested through experimentation and will be supported or refuted by the results of the experiment. B.

What stops perpetual machines

Ocean constitutes most of ___ of water a) Evaporation b) Precipitation c) Condensation d) Transpiration e) Sublimation Don't choose a random letter.

In the reaction, Zn + HCl-> ZnCl2 + H2, 25 grams Zn are reacted with 17.5 grams HCl. How many grams of H2 will be produced? A. 0.382 g of H2 B. 0.479 g of H2 C. 0.7865 g of H2 D. 0.484 g of H2

Is nail varnish soluble?

What is the periodic trend for atomic size from top and bottom in a group? From left to right in a period?

Which planets' orbits is the belt located between the main asteroid belt?