Answer:
118 elements
Explanation:
Of these 118 elements, 94 occur naturally on Earth.
Answer:
MnSO₄.7H₂O
Explanation:
To solve this question, we need to convert the mass of the dehydrated MnSO₄. The difference between mass of the hydrate and dehydrated compound is the mass of water. With the mass we can find the moles of water and the formula of the hydrate:
<em>Moles MnSO₄ -Molar mass: 151g/mol-:</em>
17.51g * (1mol / 151g) = 0.116 moles
<em>Moles H₂O -Molar mass: 18g/mol-:</em>
32.14g-17.51g = 14.63g * (1mol / 18g) = 0.813 moles
The ratio of moles MnSO₄: Moles H₂O represent the amount of water molecules in the hydrate:
0.813mol / 0.116mol = 7 molecules of water.
The hydrate formula is:
<h3>MnSO₄.7H₂O</h3>
Answer:
by increasing temperature
Answer:
The answer to your question is 0.4 moles of Oxygen
Explanation:
Data
Octane (C₈H₈)
Oxygen (O₂)
Carbon dioxide (CO₂)
Water (H₂O)
moles of water = ?
moles of Oxygen = 1
Balanced chemical reaction
C₈H₈ +10O₂ ⇒ 8CO₂ + 4H₂O
Reactant Element Products
8 C 8
8 H 8
20 O 20
Use proportions to solve this problem
10 moles of Oxygen ----------------- 4 moles of water
1 mol of Oxygen ------------------ x
x = (4 x 1) / 10
x = 4 / 10
x = 0.4 moles of water