So if you put a holo ball of paper in the water it sinks and as it sinks it gets smaller cuse pressure so it cuseus things to shrink cuse of pressure
<em>Answer: </em>D
<em>Explanation:</em>
chemical formula of methane: CH4
electron configuration of C: 2,4
electron configuration of H: 1
there are 4 hydrogen atoms that donated 1 electron each to C
therefore it's D.
Answer:
116.88g of table salt (NaCl) contains two formula units
Explanation:
Now,
We know that 1 formula unit of sodium chloride has a molar mass of 58.44g/mol
Hence;
Mass of 1 formula unit = 58.44g
Mass of x formula units = 116.88g
x = 116.88g * 1 formula unit/58.44g
x = 2 formula units
Therefore;
116.88g of table salt (NaCl) contains two formula units
Answer:
pH =3.8
Explanation:
Lets call the monoprotic weak acid HA, the dissociation equilibria in water will be:
HA + H₂O ⇄ H₃O⁺ + A⁻ with Ka = [ H₃O⁺] x [A⁻]/ [HA]
The pH is the negative log of the H₃O⁺ concentration, we know the equilibrium constant, Ka and the original acid concentration. So we will need to find the [H₃O⁺] to solve this question.
In order to do that lets set up the ICE table helper which accounts for the species at equilibrium:
HA H₃O⁺ A⁻
Initial, M 0.40 0 0
Change , M -x +x +x
Equilibrium, M 0.40 - x x x
Lets express these concentrations in terms of the equilibrium constant:
Ka = x² / (0.40 - x )
Now the equilibrium constant is so small ( very little dissociation of HA ) that is safe to approximate 0.40 - x to 0.40,
7.3 x 10⁻⁶ = x² / 0.40 ⇒ x = √( 7.3 x 10⁻⁶ x 0.40 ) = 1.71 x 10⁻³
[H₃O⁺] = 1.71 x 10⁻³
Indeed 1.71 x 10⁻³ is small compared to 0.40 (0.4 %). To be a good approximation our value should be less or equal to 5 %.
pH = - log ( 1.71 x 10⁻³ ) = 3.8
Note: when the aprroximation is greater than 5 % we will need to solve the resulting quadratic equation.
I say the answer is The ratio of oxygen atoms to hydrogen atoms in a molecule of sugar is 2 to 1
