Answer: Pumping can affect the level of the water table. In an aquifer, the soil and rock is saturated with water.
Explanation:
Answer:
17.76g
Explanation:
We need to write a balanced chemical equation for the reaction:
2Al(OH)3 + 3Ca(NO3)2 ——> 3Ca(OH)2 + 2Al(NO3)3
In the reaction above, it can be seen that 2 moles of aluminum hydroxide yielded 3 moles of calcium hydroxide. This is the theoretical viewpoint.
Now we need to know what actually happened. We need to calculate the actual number of moles of aluminum hydroxide reacted l. We can get this by dividing the mass by the molar mass.
The molar mass of aluminum hydroxide is 27+ 3( 16+1)
= 27 + 51 = 78g/mol
The number of moles is thus: 12.55/78 = 0.16 moles
Now if 2 moles of aluminum hydroxide gave 3 moles of calcium hydroxide, 0.16moles will give : (0.16*3)/2 = 0.24moles
Now we can calculate the mass of calcium hydroxide formed. The mass of calcium hydroxide formed is the number of moles multiplied by the molar mass.
The molar mass of calcium hydroxide is; 40 + 2(17) = 74g/mol
The mass is thus =74 * 0.24 = 17.76g
<span>Total mass = 2.75g
Mass % of Mg = 1.0g x 100/2.75g = 36.36 %
Mass % of O = 1.75g x 100/2.75g = 63.64 %
Mol of Mg = 36.36/24 = 1.515
Mol of O = 63.64/16 = 3.977
Ratio of Mol of Mg and O in the substance = (1.515 : 3.977) x 2 = 3 : 8
The empirical formula of substance is Mg3O8</span>
D.
The products will have at least 2 Na atoms and 1 O atom.
<h3>Further explanation</h3>
If we refer to the law of mass conservation, which states that
<em>In a closed system, the masses before and after the reaction are the same
</em>
then the number of atoms in the reactance will be the same as the number of atoms in the product
In this problem it is known that Na₂O is one of the reactants so that the product of Na atoms and O atoms will at least equal the number of atoms in the bond, namely 2 Na and 1 O
Like an example of this Na₂O reaction:
Na₂O + H₂O ⇒ 2 NaOH
Na : left =2, right = 2
O : left=2, right = 2
