What type of electron is available to form bonds?

a. valence

c. ionic

b. nucleus

d. covalent

A certain element consists of two stable isotopes. the first has a mass of 68.9 amu and a percent natural abundance of 60.4 %. the second has a mass of 70.9 amu and a percent natural abundance of 39.6 %. what is the atomic weight of the element?

Which of these are components of DNA? Select five options. deoxyribose sugar molecules ribose sugar molecules adenine phosphate molecules uracil cytosine thymine

Write the net ionic equation for the following molecular equation Mg (s) + Snso (aq) Mgso4 (aq) Sn (s) Use the lowest possible coefficients. Use the pull-down boxes to specify states such as (aa) or (s). If a box is not needed, leave it blank.)

An isotope, X, of a particular element has an atomic number of 8 and a mass number of 18. Therefore: A. X is an isotope of oxygen. B. X has 10 neutrons per atom. C. X has an atomic mass of 15.9994. D. A and B. E. A, B, and C.

What law determines that chemical equations must be balanced? What does this law say?

A 0.75mol calcium carbonate (CaCO3) pellet has what mass?

The pH of the acid in the stomach is 2. When a person has heartburn, the acid in their stomach is coming up the esophagus (lower throat) and burning the lining of the esophagus. Why would a person take an Alka Seltzer tablet for heartburn?

Calculate the photon energy (in joules) for the light emitted from the hydrogen atom if ninitial = 4 and nfinal = 2.

The distance from one place to another

What is the purpose of a cell membrane