Helium has two naturally occurring isotopes, helium-3 and helium-4. the atomic mass of helium is 4.003 amu. which isotope is more abundant in nature? explain your answer.

Across 1. the alkali metal in Period 4

If the density of lead is 11.342 what would be the volume of a 200.0 g sample of metal

The molar mass of a compound is 92 g/mol. Analysis of a sample of the compound indicates that it contains 0.606g of N and 1.390g of O. Find its molecular formula.

Consider the reaction 2 hbr (g) à h2 (g) + br2 (g) a. express the rate of the reaction in terms of the change in concentration of each of the reactants and products. b. in the first 25.0 s of this reaction, the concentration of hbr drops from 0.

If the dimensions of a cube-shaped cell with a volume of 1 pm were to double, what would be the new surface area of the cell? O A: 12 um O B. 24 uma O c. 6um O D. 3 um

What happens to the conductivity of water when an acid is dissolved in it?

How many gallons in 2 L bottle

Why can your fingernail scratch talc

Determine the molecular geometry about each interior nitrogen atom of n2h4.

Out of the following, which element has properties of both metal and nonmetal? A. Ce B. Be C. Te D. Ne