Answer:
Explanation:
Since salt is composed of two ions Na+ and Cl- it will attract to the opposite poles of the water and form a ion-dipole bond. This will cause the phenomenon freezing point depression where as the name states it will take a lower tempertature to freeze it. So instead of freezing at 0 degrees c it will freeze at a negative 2 or so on.
Answer : The molar mass of the solute would be low.
Explanation :
Formula used for depression in freezing point is:
where,
= change in freezing point
= freezing point of solution
= freezing point of water
i = Van't Hoff factor
= freezing point constant
m = molality
= mass of solute
= mass of solvent
= molar mass of solute
From the formula we conclude that, when the freezing point of the solution read incorrectly that is freezing point of the solution is lower than the true freezing point then this means that change in freezing point would be high and the molar mass of the solute would be low.
Hence, the molar mass of the solute would be low.
Answer:
713 nm. It is not visible with the naked eye.
Explanation:
Step 1: Given data
- Energy of light (E): 2.79 × 10⁻¹⁹ J
- Planck's constant (h): 6.63 × 10⁻³⁴ J.s
- Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Calculate the wavelength of the light
We will use the Planck-Einstein equation.
E = h × c / λ
λ = h × c / E
λ = 6.63 × 10⁻³⁴ J.s × 3.00 × 10⁸ m/s / 2.79 × 10⁻¹⁹ J
λ = 7.13 × 10⁻⁷ m
Step 3: Convert "λ" to nm
We will use the relationship 1 m = 10⁹ nm.
7.13 × 10⁻⁷ m × (10⁹ nm/1 m) = 713 nm
This light is not in the 400-700 nm interval so it is not visible with the naked eye.
Answer:
D
Explanation: iIt is a neutralization reaction and neutralization reaction is a reaction between and acid and base to give salt and water. In the question above, Ca(OH)2 is the base and HCl is the acid, Ca(Cl)2 is the salt and H2O.
