Water is called a universal solvent because of its ability to dissolve different types of substances.
The basic unit of life is cell and a large portion of living cell (60%) is made up of water, this is because cells need water to survive. Biochemical reactions are always ongoing in the living cells and water act as solvents under which these reactions occur. Because of the high solubility of water, it is able to dissolve various substances needed by the body, this makes it easy for the substance to participate in chemical reactions and to move from one point to another. Without water biochemical reactions will not be able to occur in cells and this will lead to the death of the cells.
The volume of the granite piece in Cm³ is 12.2 cm³
<u><em>calculation</em></u>
volume of granite = (volume of cylinder after placing granite - volume of cylinder before placing granite
= 37.2 ml - 25.0 ml = 12.2 ml
convert ml to Cm³
that is 1 ml = 1 cm³
12.2 ml = ? cm³
<em>by cross multiplication</em>
=(12.2 ml x 1 cm³) / 1 ml = 12.2 cm³
Answer:
1(a) N = 3
(b) N = 0
(c) N = 5
(d) N = -2
(2) Molecular formula for benzene is C6H6
Explanation:
1(a) N02 1-
N + (2×-2) = -1
N-4 = -1
N = -1+4 = 3
(b) N2
2(N) = 0
N = 0/2 = 0
(c) NO2Cl
N + ( 2×-2) + (-1) = 0
N - 4 - 1 = 0
N - 5 = 0
N = 0+5 = 5
(d) N2H4
2(N) + (4×1) = 0
2N + 4 = 0
2N = 0 - 4 = -4
N = -4/2 = -2
(2) Molcular mass of benzene = 78g/mole = (6×12g of carbon) + (6×1g of hydrogen) = 72+6 = 78g/mole
Therefore, molecular formula for benzene is C6H6
