Answer:
5.85 grams of NaCl should be added to 250 grams of water to make a 0.40 m solution.
Explanation:
Mass of NaCl =x
Molar mass of NaCl = 58.5 g/mol
Molality of the solution = 0.40 m
Mass of the solvent = 250 g = 0.250 kg (1g = 0.001 kg)
5.85 grams of NaCl should be added to 250 grams of water to make a 0.40 m solution.
We'll look at what happens<span> when you </span>dissolve ionic<span> and covalent </span>compounds<span> in </span>water<span>. </span>Ionic compounds<span> break apart into the </span>ions<span> that make them up, a process called dissociation, while covalent </span>compounds only break into the molecules, not the individual atoms.<span>When you immerse an </span>ionic compound<span> in </span>water<span>, the ions are attracted to the </span>water <span>molecules, each of which carries a polar charge. If the attraction between the ions and the </span>water <span>molecules </span>is<span> great enough to break the bonds holding the ions together, the compound </span><span>dissolves</span>
Answer:
The correct answer is 0.92 g
Explanation:
The density is defined as the mass per unit of volume:
Density= mass/volume
From the data provided:
volume= 5.4 L
density= 0.17 g/L
Thus, to calculate the mass of helium:
mass= density x volume = 0.17 g/L x 5.4 L= 0.918 g ≅ 0.92 g
Mg(OH)2
Mg: 1
O: 2
H: 2
Mg. O H
24.3g 32g. 2
58.3g in 1 mol of Mg(OH)2
3.2mol of Mg(OH)2 x 58.3g of Mg(OH)2
-------------------------
1 mol of Mg(OH)2
= 186.56 g of Mg(OH)2 in 3.2 mols of Mg(OH)2
