Answer:
There will be produced 1.71 moles of B which contain 1.03×10²⁴ molecules
Explanation:
The example reaction is:
2A → 3B
2 moles of A produce 3 moles of B
If we have the mass of A, we convert it to moles and then, we make the rule of three: 29.2 g / 25.6g/mol = 1.14 moles
Therefore 2 moles of A produce 3 moles of B
1.14 moles of A will produce (1.14 . 3) / 2 = 1.71 moles of B are produced
Now we can determine, the number of molecules
1 mol has NA molecules (6.02×10²³)
1.71 moles have (1.71 . NA) = 1.03×10²⁴ molecules
That looks like cells of a multicellular organism, so B.
Answer:
- <u>Alkaline or basic solution </u>(alkaline and basic means the same)
Explanation:
According to the <em>pH</em>, solutions may be classified as neutral, acidic, or alkaline (basic).
This table shows such classification:
pH classification
7 neutral
> 7 alkaline or basic
< 7 acidic
Thus, since the pH of the solution is 8.3, which is greater than 7, the solution is classified as basic (alkaline).
Additionally, you must learn that pH is a logarithmic scale for the concentration of hydronium ions in the solution.
You can calculate the concentration of hydronium ions using antilogarithm properties:
![pH=-log[H_3O^+]\\ \\ {[H_3O^+]}=10^{-pH}\\ \\ {[H_3O^+]}=10^{-8.3}=0.00000000501](https://tex.z-dn.net/?f=pH%3D-log%5BH_3O%5E%2B%5D%5C%5C%20%5C%5C%20%7B%5BH_3O%5E%2B%5D%7D%3D10%5E%7B-pH%7D%5C%5C%20%5C%5C%20%7B%5BH_3O%5E%2B%5D%7D%3D10%5E%7B-8.3%7D%3D0.00000000501)
NaOH solutions are alkaline solutions, bases, according to Arrhenius model, because they contain OH⁻ ions and release them when ionize in water.
Answer:
a.
Turn paper Blue - these are alkaline/ base substances.
Turn paper Red - these substances are acidic in nature.
- Lemon Juice
- Vinegar
- Cola drink
b. i. A wasp sting - Lemon juice
ii. A bee sting - Toothpaste
iii. A wasp sting is alkaline which means that running an acidic substance like lemon or lemon juice on it should neutralize it.
A bee sting is acidic so an alkaline substance such as toothpaste should neutralize it as well.
