Which of the following is not a property of an acid?
select one:
a. an acid is corrosive.
b. an acid tastes sour.
c. an acid turns red litmus paper blue.
d. an acid reacts with metals and carbonates.

D it's not mostly correct as acid can't react whith other metal let's say for hydrochloric acid or nitric acid and aluminum or zinc

As they for an oxide coat which prevent further reaction

Also option C must be vice versa

i just got this problem. it's 90.3

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.