Answer:
0.0199moles
Explanation:
The number of miles of a substance can be calculated using the formula:
Number of moles (n) = Mass (M) / Molar mass (MM)
In this question, the mass of Magnesium element (Mg) = 0.478 g while the atomic mass is 24
Therefore, number of moles of Magnesium is:
Moles = 0.478/24
Moles = 0.01992
Hence, 0.0199 moles of Magnesium are contained in 0.478 g of the element.
mass = Density x Volume
2.00 x 0.160 = 0.32 grams
Oxygen is the second most abundant gas in our atmosphere.
Answer: Change in chemical composition of reactants is an event which must always occur for a chemical reaction to take place.
Explanation:
A chemical reaction is defined as a reaction in which there will always occur change in chemical composition of reactant species.
For example,
Here, chemical composition of both and HCl changes which leads to the formation of silver chloride and nitric acid. Hence, it is a chemical reaction.
Therefore, we can conclude that change in chemical composition of reactants is an event which must always occur for a chemical reaction to take place.
Volume of Ba(OH)₂ : 0.363 L
<h3>Further explanation</h3>
Balanced equation :
H₂(g)+S(s)+2OH⁻(aq)⇒ S²⁻(aq)+2H₂O(l) (eq 1)
Ba(OH)₂⇒Ba²⁺+2OH⁻ (eq 2)
mol S :
mol OH from eq 1 : (mol S : mol OH = 1 : 2)
mol Ba(OH)₂ from eq 2 : (mol Ba(OH)₂ : mol OH⁻=1 : 2)
volume of Ba(OH)₂ :