though alchemists were often superstitious, they left a rich legacy of modern chemists. what was their main contribution-
Explanation:
they were the first to preform experiments.
Answer:
5.62 * 10^-13 moles per liter
Explanation:
The pH of a solution is the negative logarithm to base 10 of the concentration of hydrogen ions. What we simply do here is to input the information in the question into the equation:
pH=−log10[H⁺]
Here we know the pH but we do not know the concentration of the hydrogen ions.
12.25 = -log [H+]
log[H+] = -12.25
[H+] = 10^-12.25
[H+] = 5.62 * 10^-13 moles per liter
Element which possess different number of "Neutrons" in different situations could be an isotope of the atom
Ex. - 17 Cl 34, 17 Cl 35, 17 Cl 36
They all the isotopes.
Hope this helps!
Answer:
-4.59°C
Explanation:
Let's see the formula for freezing point depression.
ΔT = Kf . m . i
ΔT = Freezing T° of pure solvent - Freezing T° of solution
Kf = Freezing constant. For water if 1.86°C/m
m = molality (moles of solute in 1kg of solvent)
i = Van't Hoff factor.
0°C - Freezing T° of solution = 1.86°C /m . 1.30m . 1.9
Freezing T° of solution = - (1.86°C /m . 1.30m . 1.9)
Freezing T° of solution = - (1.86°C/m . 1.30m . 1.9) → -4.59°C
NaCl → Na⁺ + Cl⁻
