Answer:
Valency is defined as the number of hydrogen atoms which combine directly or indirectly with one atom of an element.
Example:
One atom of nitrogen combines with three atoms of hydrogen to form ammonia gas. So, the valency of nitrogen is 3.
Answer:
781×10¯² g of MgCl₂.
Explanation:
The balanced equation for the reaction is given below:
Mg + 2HCl —> MgCl₂ + H₂
Next, we shall determine the mass of HCl that reacted and the mass of MgCl₂ produced from the balanced equation. This is illustrated below:
Molar mass of HCl = 1 + 35.5
= 36.5 g/mol
Mass of HCl from the balanced equation = 2 × 36.5 = 73 g
Molar mass of MgCl₂ = 24 + (35.5×2)
= 24 + 71
= 95 g/mol
Mass of MgCl₂ from the balanced equation = 1 × 95 = 95 g
SUMMARY:
From the balanced equation above,
73 g of HCl reacted to produce 95 g of MgCl₂.
Finally, we shall determine the mass of MgCl₂ produced by the reaction of 6 g of HCl. This can be obtained as follow:
From the balanced equation above,
73 g of HCl reacted to produce 95 g of MgCl₂.
Therefore, 6 g of HCl will react to produce = (6 × 95)/73 = 781×10¯² g of MgCl₂.
Thus, 781×10¯² g of MgCl₂ were obtained from the reaction.
An oxide of nitrogen contains 30.45 mass % N, if the molar mass is 90± 5 g/mol the molecular formula is N₂O₄.
<h3>What is molar mass?</h3>
The molar mass of a chemical compound is determined by dividing its mass by the quantity of that compound, expressed as the number of moles in the sample, measured in moles. A substance's molar mass is one of its properties. The compound's molar mass is an average over numerous samples, which frequently have different masses because of isotopes.
<h3>How to find the molecular formula?</h3>
The whole-number multiple is defined as follows.
Whole-number multiple = 
The empirical formula mass is shown below.
Mw of empirical formula = Mw of N+ 2 x (Mw of O)
= 14.01 g/mol + 2 x (16.00 g/mol)
= 46.01 g/mol
With the given molar mass or the molecular formula mass, we can get the whole-number multiple for the compound.
Whole-number multiple = 
≈ 2
Multiplying the subscripts of NO2 by 2, the molecular formula is N(1x2)O(2x2)= N2O4.
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False. An increase in temperature is an exothermic reaction. However, when a temperature decreases this is known as an endothermic reactionz
Answer:
How the relative density of a substance is related to the density calculate the density of iron if its relative density is 2 and a density of water is 2gcm -3
R.d= relative density of substance/ relative density of water
R.d= 2/2
R.d= 1gcm-3
Explanation:
