Answer:
13.2 g of gold
Explanation:
We'll begin by converting 5.25 L to ft³.
This can be obtained as follow:
Recall:
1 L = 0.0353 ft³
Therefore,
5.25 L = 5.25 × 0.0353
5.25 L = 1.85×10¯¹ ft³
From the question given above,
2.45 g of gold is present in 5.25 L ( i.e 1.85×10¯¹ ft³) of soil.
Therefore, Xg of gold will be present in 1 ft³ of soil i.e
Xg of gold = 2.45/1.85×10¯¹
Xg of gold = 13.2 g
Therefore, 13.2 g of gold is present in 1 ft³ of the soil.
When a molecule of oxygen (O2) is combined with an atom of carbon (C), they form CO2, or carbon dioxide. The carbon and oxygen are the reactants in this chemical reaction; the CO2 is the product.
The reason why some water and heat are added after Mg ribbon is reacted completely with air is to remove Mg3N2 as MgO.
Combustion reaction is a reaction in which a substance is completely burnt in oxygen. Magnesium ribbon can be converted to magnesium oxide by combustion in air.
The reaction is as follows; 2Mg(s) + O2 ----> 2MgO(s)
Since air contains nitrogen, Mg3N2 is also formed. Heat and water can be added to the reaction thereby converting magnesium nitride to magnesium oxide.
Learn more: brainly.com/question/11527546
Answer:
39.3%
Explanation:
CaF2 + H2SO4 --> CaSO4 + 2HF
We must first determine the limiting reactant, the limiting reactant is the reactant that yields the least number of moles of products. The question explicitly says that H2SO4 is in excess so CaF2 is the limiting reactant hence:
For CaF2;
Number of moles reacted= mass/molar mass
Molar mass of CaF2= 78.07 g/mol
Number of moles reacted= 11g/78.07 g/mol = 0.14 moles of Calcium flouride
Since 1 mole of calcium fluoride yields two moles of 2 moles hydrogen fluoride
0.14 moles of calcium fluoride will yield 0.14×2= 0.28 moles of hydrogen fluoride
Mass of hydrogen fluoride formed (theoretical yield) = number of moles× molar mass
Molar mass of hydrogen fluoride= 20.01 g/mol
Mass of HF= 0.28 moles × 20.01 g/mol= 5.6 g ( theoretical yield of HF)
Actual yield of HF was given in the question as 2.2g
% yield of HF= actual yield/ theoretical yield ×100
%yield of HF= 2.2/5.6 ×100
% yield of HF= 39.3%