Answer:
1) -COOH
2) -NH2
3) hydrogen bonds
4) dispersion forces
5) -CH3
6) hydrogen bonds
7) negative
8) negative
9) positive
Explanation:
Alanine has a <u>-COOH</u> and a <u>-NH2</u> group available to form <u>hydrogen bonds</u> with water molecules.
Although there are some potential <u>dispersion forces</u> between the terminal <u>-CH3</u> group of alanine and hexane molecules, we expect the <u>hydrogen bonds</u> between alanine and water to be stronger.
Stronger intermolecular attractive forces between alanine and water lead to a more <u>negative ΔHmix</u> and more <u>negative (smaller positive)</u> ΔHsoln for water than for hexane.
It will sink below the surface. Since dish soap is a surfactant, it will alter the water's surface tension. Lowering the surface tension, the water will no longer be able to support the mass of the twig.
65. The atomic number is the number of protons in the atom.
Answer:
4.99 × 10³ g/mol
Explanation:
Step 1: Given and required data
- Mass of the covalent compound (m): 62.4 g
- Volume of the solution (V): 1.000 L
- Osmotic pressure (π): 0.305 atm
- Temperature (T): 25°C = 298 K
Step 2: Calculate the molarity (M) of the solution
The osmotic pressure is a colligative pressure. For a covalent compound, it can be calculated using the following expression.
π = M × R × T
M = π / R × T
M = 0.305 atm / (0.0821 atm.L/mol.K) × 298 K
M = 0.0125 M
Step 3: Calculate the moles of solute (n)
We will use the definition of molarity.
M = n / V
n = M × V
n = 0.0125 mol/L × 1.000 L = 0.0125 mol
Step 4: Calculate the molar mass of the compound
0.0125 moles of the compound weigh 62.4 g. The molar mass is:
62.4 g/0.0125 mol = 4.99 × 10³ g/mol
