Answer:
9Be
4
Explanation:
Atomic number = (3+2)-1= 4
Mass number = (6+4)-1 =9
<span>7.379 * 10^(-4) is measured, hence prone to error, either human error or via measuring device. In this case,
100 cm = 1 m is written in stone and is unquestionable.
The density of the gold is 19.3 g/cm^3 and could be an approximation.
The approximation is good to at least one night.</span>
Answer:
= 29.64 g NaNO3
Explanation:
Molarity is given by the formula;
Molarity = Moles/Volume in liters
Therefore;
Number of moles = Molarity × Volume in liters
= 1.55 M × 0.225 L
= 0.34875 moles NaNO3
Thus; 0.34875 moles of NaNO3 is needed equivalent to;
= 0.34875 moles × 84.99 g/mol
= 29.64 g
Answer:
Molarity of Na₂CO₃ = 0.25M
% mass = 2.69
Explanation:
Molarity means mole of solute in 1L of solution
Molar mass of solute (Na₂CO₃) = 105,98 g/m
Moles = mass / molar mass → 6.73 g / 105.98 g/m = 0.0635 m
Mol/L = [M]
0.0635 mol/0.250L = 0.25M
Density of solution = Solution mass / Solution volume
1 g/ml = Solution mass / 250 mL → Solution mass is 250g
% mass will be:
In 250 g of solution we have 6.73 g of solute
in 100 g of solution we have (100 . 6.73)/250 = 2.69
