The mass numbers for two isotopes are unequal because they have different numbers of NEUTRONS.
Answer:
A. 6N
B. 4H, 2O
C. 4H, 4N, 12O
D. 2Ca, 4O, 4H
E. 3Ba, 6Cl, 18O
F. 5Fe, 10N, 30O
G. 12Mg, 8P, 32O
H. 4N, 16H, 2S, 8O
I. 12Al, 18Se, 72O
J. 12C, 32H
I am 90% sure this is correct
Answer:
mass of HNO₃ = 0.378 g
Explanation:
Normality = Molarity * number of equivalents
Molarity = Normality/number of equivalents
normality of HNO₃ = 0.30 N, Volume = 20 mL
HNO₃ ionizes in the following way:
HNO₃(aq) ----> H⁺ + NO₃⁻
Therefore, number of equivalents for HNO₃ is 1
molarity of HNO₃ = 0.30/1 =0.30 mol/dm³
Using the formula, molarity = number of moles/volume in liters
number of moles = molarity * volume
Number of moles of HNO₃ = 0.30 mol/dm³ * 20ml * 1 dm³ /1000 mL
number of moles = 0.006 moles
From the formula, mass = number of moles * molar mass
molar mass of HNO₃ = 63.0 g/mol
mass = 0.006 * 63
mass of HNO₃ = 0.378 g
