Answer:
Photosynthesis transforms light energy into chemical energy by making sugars. Cellular respiration releases the chemical energy from food by breaking down sugars.
Explanation:
I'm actually learning this in school right now
Hope this helps!
~PurpleMist
Answer:
See below
Step-by-step explanation:
You won't see much happening. The solution is saturated, so the salt will fall to the bottom of the container and sit there. It will not dissolve.
However, at the atomic level, Na⁺ and Cl⁻ ions are being pulled from the surface of the crystals and going into solution as hydrated ions. At other places, Na⁺ and Cl⁻ ions are returning to the surface of the crystals.
The process is
NaCl(s) ⇌ Na⁺(aq) + Cl⁻(aq)
The rates of the forward and reverse processes are equal, so you see no net change.
First, we need to get the value of Ka:
when Ka = Kw / Kb
we have Kb = 1.8 x 10^-5
and Kw = 3.99 x 10^-16 so, by substitution:
Ka = (3.99 x 10^-16) / (1.8 x 10^-5) = 2.2 x 10^-11
by using the ICE table :
NH4+ + H2O →NH3 + H+
intial 0.013 0 0
change -X +X +X
Equ (0.013-X) X X
when Ka = [NH3][H+] / [NH4+]
by substitution:
2.2 x 10^-11 = X^2 / (0.013 - X) by solving this equation for X
∴X = 5.35 x 10^-7
∴[H+] = X = 5.35 x 10^-7
∴PH = - ㏒[H+]
= -㏒(5.35 x 10^-7)
= 6.27
Answer:
Sand has a strong non-polar covalent connection, that prevents water to break it down.
Explanation:
Sand being composed of quartz and small particulars of minerals can only be dissolved in hot acids, unlikd sugar which can easily be broken down by water, due to the large magnetic molecular propery of water and the ability to evolve sugar in an Intermolecular manner.
Answer: B) 46.7% Si and 53.3% O
Explanation:
To calculate the mass percent of element in a given compound, we use the formula:

Mass of quartz
= 5.05 g
Mass of silicon = 2.36 g
Mass of oxygen = Mass of quartz
- mass of silicon = 5.05g - 2.36 g = 2.69 g


Thus the percentages of silicon and oxygen in quartz are B) 46.7% Si and 53.3% O