How is a mixture different from a compound? a. Mixtures are commonly found in nature.

b. Solids, liquids, and gases can form mixtures.

c. Mixtures have two or more components.

d. Each substance in a mixture keeps most of its characteristic properties.

I think the answer is d. Each substance in a mixture keeps most of its characteristic properties.

C

Explanation:

Compounds are formed because of chemical bonding between two elements and Mixtures are formed when substances are physically mixed with one another. A mixture contains two or more types of pure substances (elements or compounds) moved physically not chemically; they do not contain any atomic bonds.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.