Answer: ⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫⚫
Explanation:
Answer:
0.576M and 0.655m
Explanation:
<em>...Dissolves 15.0g of styrene (C₈H₈) in 250.mL of a solvent with a density of 0.88g/mL...</em>
<em />
Molarity is defined as moles of solute (Styrene in this case) per liter of solution whereas molality is the moles of solute per kg of solvent. Thus, we need to find the moles of styrene, the volume in liters of the solution and the mass in kg of the solvent as follows:
<em>Moles styrene:</em>
Molar mass C₈H₈:
8C = 12.01g/mol*8 = 96.08g/mol
8H = 1.005g/mol* 8 = 8.04g/mol
96.08g/mol + 8.04g/mol = 104.12g/mol
Moles of 15.0g of styrene are:
15.0g * (1mol / 104.12g) = 0.144 moles of styrene
<em>Liters solution:</em>
250mL * (1L / 1000mL) = 0.250L
<em>kg solvent:</em>
250mL * (0.88g/mL) * (1kg / 1000g) = 0.220kg
Molarity is:
0.144 moles / 0.250L =
<h3>0.576M</h3>
Molality is:
0.144 moles / 0.220kg =
<h3>0.655m</h3>
The number of H atoms in 3(NH₄)₂CrO₄ = 24
<h3>Further explanation </h3>
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
(empirical formula) n = molecular formula
Subscripts in the chemical formula indicate the number of atoms
The compound of 3(NH₄)₂CrO₄ ( 3 molecules of (NH₄)₂CrO₄ ) :
Number of H :
Answer:
The atomic mass is the average number of protons and neutrons for all natural isotopes of an element. It is a decimal number.
Explanation:
Atomic Mass and Mass Number Example
:
Hydrogen has three natural isotopes: 1H, 2H, and 3H. Each isotope has a different mass number.
1H has 1 proton. Its mass number is 1. 2H has 1 proton and 1 neutron. Its mass number is 2. 3H has 1 proton and 2 neutrons. Its mass number is 3. 99.98% of all hydrogen is 1H 0.018% of all hydrogen is 2H 0.002% of all hydrogen is 3H Together, they give a value of atomic mass of hydrogen equal to 1.0079 g/mol.
1. Cylinder
2. Sphere
3. Rectangular prism
4. Cone
Hope this can help.
