What is the mass in amu of 635 atoms of hydrogen?

What prefixes is best for measuring large quantities like the mass of a person?

Which atom has the least attraction for the electrons in a bond between that atom and an atom of hydrogen? (1) carbon (2) nitrogen (3) oxygen (4) fluorine

Which of the following is a chemical property of water? boils at 100 °C Has a density of 1 gm/mL Is liquid at room temperature Reacts with pure sodium

If the air had 2 grams of vapor what would the percentage of the relative humidity

Is the following salt an acid, base, or neutral? NH4ClO4

The atomic number of calcium (Ca) is 20, and it's mass number is 40. What is true about the subatomic particles that make up a neutral atom of calcium? A) It has 20 protons, 20 neutrons and 20 electrons.

Explain why a sidewalk has built-in cracks every few feet?

How many periods does the periodic table have? 7 18 9 8

Which one is correct A. It allowed them to escape B. It allowed them to chase down C. It allowed them to reach food D. All of these

A 20.0 mL sample of hydrochloric acid was neutralized with 58.4 mL of 0.250 M NaOH, in a titration. a. Write the balanced chemical equation for the reaction, b. What is the concentration of the hydrochloric acid?