The molality of a solute is equal to the moles of solute per kg of solvent. We are given the mole fraction of I₂ in CH₂Cl₂ is <em>X</em> = 0.115. If we can an arbitrary sample of 1 mole of solution, we will have:
0.115 mol I₂
1 - 0.115 = 0.885 mol CH₂Cl₂
We need moles of solute, which we have, and must convert our moles of solvent to kg:
0.885 mol x 84.93 g/mol = 75.2 g CH₂Cl₂ x 1 kg/1000g = 0.0752 kg CH₂Cl₂
We can now calculate the molality:
m = 0.115 mol I₂/0.0752 kg CH₂Cl₂
m = 1.53 mol I₂/kg CH₂Cl₂
The molality of the iodine solution is 1.53.
Answer:
Xenon
Explanation:
Step 1: Given data
- Pressure (P): 1.00 atm (I looked it up)
Step 2: Convert the temperature to Kelvin
K = °C + 273.15 = 100.0°C + 273.15 = 373.2 K
Step 3: Calculate the number of moles (n)
We will use the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 1.00 atm × 0.335 L / (0.0821 atm.L/mol.K) × 373.2 K
n = 0.0109 mol
Step 4: Calculate the molar mass of the gas
M = 1.44 g / 0.0109 mol = 132 g/mol
Step 5: Identify the gas
The gas with a molar mass of about 132 g/mol is xenon.
Calcium carbonate contains the carbonate ion. Citric acid is an acid. When an acid reacts with a carbonate, carbon dioxide gas is one of the products. Carbon dioxide gas produces the fizzing effect in water.
To convert grams to atoms, we first need to find the moles and then multiply by Avogadro's constant.
0.1310 g * (1 mol/22.99 g) * (6.022*10^23 atom/1 mol) = 3.431 *10^21 atoms.
Answer = c
Conservation of mass (mass is never lost or gained in chemical reactions), during chemical reaction no particles are created or destroyed, the atoms are rearranged from the reactants to the products.
