Answer:
1 g
Explanation:
The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.
We can make a table of the mass left after each half-life.
The mass remaining after 48 h is 1 g.
Answer:
atom are very tiny partical
Answer:
Mass = 65.8 g
Explanation:
Given data:
Mass of sodium chloride = ?
Volume of solution = 1.5 L
Molarity of solution = 0.75 M
Solution:
Number of moles of sodium chloride:
Molarity = number of moles / volume in L
By putting values,
0.75 M = number of moles = 1.5 L
Number of moles = 0.75 M × 1.5 L
Number of moles = 1.125 mol
Mass of sodium chloride:
Mass = number of moles × molar mass
Mass = 1.125 mol × 58.5 g/mol
Mass = 65.8 g
Answer:
1.70
Explanation:
The molar mass of perchloric acid is 100.46 g/mol. The moles corresponding to 484 mg (0.484 g) are:
0.484 g × (1 mol/100.46 g) = 4.82 × 10⁻³ mol
4.82 × 10⁻³ moles are dissolved in 240 mL (0.240 L) of solution. The molar concentration of perchloric acid is:
4.82 × 10⁻³ mol/0.240 L = 0.0201 M
Perchloric acid is a strong monoprotic acid, that is, it dissociates completely, so [H⁺] = 0.0201 M.
The pH is:
pH = -log [H⁺] = -log 0.0201 = 1.70
Answer:
i need a picture or more info to understand
