The answer is A. you sre correct!
Answer:
N = n× l
N = number of entities
n= moles
l = Avogadro's constant = 6.023 × 10^23
3.01 × 10^ 23 = n * 6.023 × 10^23
n = 3.01 × 10^23/6.023 × 10^23
n= 0.5moles
Molar mass = mass/ number of moles
Molar mass = 56
mass = 56 × 0.5
= 28g
Hope this helps.
The reactivity of metals increases as you move left in a period and as you move down in a group, so Marie needs to know the period and group of the element inside each box. Boxes that show locations in groups 1 or 2 or in period 8 contain the most reactive elements.
Answer:
Total percent of magnesium in sample = 25.5%
Explanation:
Given:
Mass of magnesium = 24 gram
Mass of chlorine = 70 gram
Find:
Total percent of magnesium in sample = ?
Computation:
Total mass of sample = Mass of magnesium + Mass of chlorine
Total mass of sample = 24 gram + 70 gram
Total mass of sample = 94 gram
Total percent of magnesium in sample = [Mass of magnesium / Total mass of sample]100
Total percent of magnesium in sample = [24/94]100
Total percent of magnesium in sample = [0.255]100
Total percent of magnesium in sample = 25.5%