Answer:
24.32
Explanation:
From the question given above, the following data were obtained:
Isotope A:
Mass of A = 24
Abundance (A%) = 78.70%
Isotope B
Mass of B = 25
Abundance (B%) = 10.13%
Isotope C:
Mass of C = 26
Abundance (C%) = 11.17%
Average atomic mass of Mg =..?
The average atomic mass of Mg can be obtained as illustrated below:
Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
Average atomic mass = [(24 × 78.70)/100] + [(25 × 10.13)/100] + [(26 × 11.17)/100]
= 18.888 + 2.5325 + 2.9042
= 24.3247 ≈ 24.32
Therefore, the average atomic mass of magnesium (Mg) is 24.32
Answer:
The excited state electron configuration of an atom indicates the promotion of a valence electron to a higher energy state.
After 3 half life periods you would have 5 grams of krypton left because half of 40 is 20 half of 20 is 10 and half of 10 is 5
Answer:
22.46
Explanation:
.There are 3.79 liters in one gallon
88.98 %
The Balance Chemical Equation is as follow,
2 HCl + Pb(NO₃)₂ → 2 HNO₃ + PbCl₂
According to equation,
331.2 g (1 mole) Pb(NO₃)₂ produces = 278.1 g (1 mole) PbCl₂
So,
870 g of Pb(NO₃)₂ will produce = X g of PbCl₂
Solving for X,
X = (870 g × 278.1 g) ÷ 331.2 g
X = 730.5 g of PbCl₂
Therefore,
Theoretical Yield = 730.5 g
Also as given,
Actual Yield = 650 g
So using following formula for percentage yield,
%age Yield = (Actual Yield / Theoretical Yield) × 100
Putting values,
%age Yield = (650 g / 730.5 g) × 100
%age Yield = 88.98 %
Brianliest please and thank you.