Which of the following chemical symbols represents the element sodium?

a. s

b. n

c. sc

d. na

A. What is the mass number of an alpha particle? b. What is the identity of an alpha particle? c. What kind of charge does an alpha particle have?

How many nonbonding electrons does phosphorus have

If one amino acid in a protein sequence is changed, what could happen? A. It could become a carbohydrate. B. Normal bodily functions can change. C. Proteins are so complex that one amino acid won't make a difference.

How many neutrons does element X have if its atomic number is 31 and its mass number is 80?

In a compound, chemical energy is contained in the?

Which physical method can be used for obtaining a sample of salt from a small beaker of salt water? boiling freezing chromatography sorting

Science is a unique field of thought because it relies on to describe the world. •Observations and experim •Teachers and students •Books and writings •Scientists and statements

Hemoglobin, a protein in red blood cells, carries o2 from the lungs to the body's cells. iron (as ferrous ion, fe2+) makes up 0.33 mass % of hemoglobin. if the molar mass of hemoglobin is 6.8 Ã 104 g/mol, how many fe2 + ions are in one molecule?

What could you predict about a methane molecule that would most likely be made by using both the quantum model of the atom and John Dalton's model?

What is the molar mass of an unknown hydrocarbon whose density is measured to be 1.97 g/l at stp?