Formula: molality, m = n solute / kg solvent
n solute = # of moles of solute = mass(g) / molar mass
Molar mass of Mg Br2 = 184.11 g/mol
m = [46g / 184.11 g/mol] / 0.5 kg = 0.50 mol/kg
4 l ------ 3,2 g
x l ------ 8 g
x = 8 g × 4 l / 3,2 g = 10 l
Answer: 10 l of sulfuric acid is needed to produce 8 g of product.
:-) ;-)
A compound is a pure substance composed of two or more different atoms chemically bonded to one another. A compound can be destroyed by chemical means. It might be broken down into simpler compounds, into its elements or a combination of the two.
Answer: acetone molecule ( CH₃-CO-CH₃)
Explanation:
1) Acetone is CH₃-CO-CH₃
2) That is a molecule (build up of covalent bonds).
3) When dissolved, covalent bonded compounds remain as separate molecules, then it is said that the major species present in the solution is the molecule. The molecules of acetone are surrounded (sovated) by the molecules of water.
This as opposed to the case of ionic compounds that ionize. When a compound as NaCl dissolves in water, it ionizes completely, so the major speceies are not NaCl formulas, but the ions Na⁺ and Cl⁻, not molecules.
That leads to the answer: the major species present when acetone is dissolved in water is the molecules of acetone (you do not need to state the fact that the molecules of water are part of the solution, because that is not the target of the question).
Answer:
pressure and temperature are directly proportional.
Explanation:
At constant temperature and pressure the volume of a gas is directly proportional to the number of moles of gas. Also given a constant temperature and volume the pressure of a gas is directly proportional to the number of moles of gas.
This means that if V is constant then
P = n (RT/V) then n= PV/RT. As P is increased, T is also increased thereby decreasing the value of n since pressure and temperature are directly proportional.