Answer: The molarity of a solution that is 26.0% by mass in phosphoric acid is 3.06 M
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
n = moles of solute
=volume of solution in ml
Given : 26.0 g of phosphoric acid in 100 g of solution.
To calculate the moles, we use the equation:
Volume of solution =
Molarity of a solution that is 26.0% by mass in phosphoric acid is 3.06 M
Answer:
4.82 g
Explanation:
To solve this problem we'll use the <em>definition of molarity</em>:
- Molarity = moles / liters
We are given the volume and concentration (keep in mind that 100mL=0.100L):
- 0.825 M = moles / 0.100 L
Now we <u>calculate the number of NaCl moles required</u>:
Then we convert 0.0825 NaCl moles into grams, using its molar mass:
- 0.0825 mol * 58.44 g/mol = 4.82 g
1.Products of most combustion reactions are:
Carbon dioxide and water
2.Alloys are made by melting and combining metals together.
Chemical changes involve electrons,in this process no electron is used/shared or given.
Thus,its not a chemical change.
Answer:
146 g/mol → option b.
Explanation:
This is a problem about the freezing point depression. The formula for this colligative property is:
ΔT = Kf . m . i
We assume i = 1, so our compound is not electrolytic.
ΔT = Freezing T° of pure solvent - Freezing T° of solution = 1.02 °C
m = molality (mol of solute/kg of solvent)
We convert the grams of solvent (benzene) to kg → 250 g . 1 kg/1000 = 0.250 kg.
We replace → 1.02°C = 5.12°C/mol/kg . mol/ 0.250kg . 1
1.02°C / 5.12 mol/kg/°C = mol/ 0.250kg
0.19922 mol/kg = mol/ 0.250kg
mol = 0.19922 . 0.250kg → 0.0498 mol
molar mass = g/mol → 7.27 g / 0.0498mol = 146 g/mol
The first part of two is heat, not temperature, once that is cleared up: starting from 3: temperature, concentration, collisions, catalytic converter, surface area
