Elements, Molecules and cells

Question 1

what is the smallest unit of an element

Answer 1

the atom

Question 2

what charge does a proton have

Answer 2

positive electrical charge

Question 3

what charge does a neutron have

Answer 3

no charge

Question 4

how many elements are known to make up living organisms

Answer 4

26 elements

Question 5

when two atoms share electrons it is a ……. bond

Answer 5

covalent

Question 6

the number of bonds an atom can form is determined by

Answer 6

the distribution of electrons in its atomic orbitals

Question 7

what is an organic compound

Answer 7

a compound containing carbon

Question 8

what is an inorganic compound

Answer 8

a compound which doesn’t contain water

Question 9

what is a structural formula

Answer 9

details the way in which atoms are connected in a compound

Question 10

what are molecules electrical standing

Answer 10

neutral

Question 11

why is a molecule or ion called a radical

Answer 11

when it has an unpaired electron

Question 12

what principle is involved in reactions

Answer 12

principle of mass conservation (atoms are rearranged not lost/gained)

Question 13

what does pH describe

Answer 13

the concentration of protons of H+ in a solution