Answer:
An acid dissociation constant, K a, (also known as acidity constant, or acid-ionization constant) is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction ↽ − − ⇀ − + + known as dissociation in the context of acid–base reactions.
Explanation:
Answer:

Explanation:
We need to use the formula for heat of vaporization.

Identify the variables.
- The heat absorbed by the evaporating water is the <u>latent heat of vaporization. </u>For water, that is 2260 Joules per gram.
- Q is the energy, in this problem, 50,000 Joules.
- m is the mass, which is unknown.

Substitute the values into the formula.

We want to find the mass. We must isolate the variable, m.
m is being multiplied by 2260 J/g. The inverse operation of multiplication is division. Divide both sides by 2260 J/g.


Divide. Note that the Joules (J) will cancel each other out.


Round to the nearest whole number. The 1 in the tenth place tells us to leave the number as is.

The mass is about 22 grams, so choice B is correct.
Answer:
0.302 moles
Explanation:
Data given
Mass of Pb(NO₃)₂ = 100 g
Moles of Pb(NO₃)₂ = ?
Solution:
To find mole we have to know about molar mass of Pb(NO₃)₂
So,
Molar mass of Pb(NO₃)₂ = 207 + 2[14 + 3(16)]
= 207 + 2[14 + 48]
= 207 + 124
Molar mass of Pb(NO₃)₂ = 331 g/mol
Formula used :
no. of moles = mass in grams / molar mass
Put values in above formula
no. of moles = 100 g / 331 g/mol
no. of moles = 0.302 moles
no. of moles of Pb(NO₃)₂ = 0.302 moles
Answer:
In general, print publications with authors and listed sources tend to be reliable because they provide sources which readers can verify. Likewise, Web postings with a .gov (posted by the United States government) are both current and reliable.
Explanation:
Answer:
Refracted (refraction) – the bending of transmitted light as it travels across the boundary of one material into another material in which it's speed is different. Unlike diffraction, this change in direction of light occurs because light is changing its speed in the different substances in it traveling in.
Explanation:
Hope it helps