Answer:
Mass = 8 g
Explanation:
Given data:
Mass of MgO formed = 20 g
Mass of oxygen needed = ?
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of MgO:
Number of moles = mass/molar mass
Number of moles = 20 g/ 40 g/mol
Number of moles = 0.5 mol
Now we will compare the moles of MgO and O₂ from balance chemical equation:
MgO : O₂
2 : 1
0.5 : 1/2×0.5 = 0.25 mol
Mass of oxygen required:
Mass = number of moles × molar mass
Molar mass of O₂ is 32 g/mol
Mass = 0.25 mol × 32 g/mol
Mass = 8 g
Answer:
30 cm³
Explanation:
Step 1: Given data
- Density of aluminum (ρ): 2.7 g/cm³
- Mass of aluminum (m): 81 g
- Volume occupied by aluminum (V): ?
Step 2: Calculate the volume occupied by aluminum
The density of aluminum is equal to its mass divided by its volume.
ρ = m/V
V = m/ρ
V = 81 g / 2.7 g/cm³
V = 30 cm³
Answer:
A. Solution, Colloid, Suspension
Hope i could help
I might be wrong but I think its 2 then 4 then 8