The pH scale was given by Sorensen to quanitatively define strength of an acid and base
the pH scale extends from 0 to 14
For acids
The pH should be less than 7 [always]
For base
The pH should be more than 7 [always]
The pH seven is of neutral solution
pH = -log[H+]
Thus lower the pH higher the concentration of hydronium ion or protons produced by an acid
thus for the given pH scale interval [0-3] it represents strong acid [Which will give high concentration of protons on dissociation]
Answer:
Option D.
Explanation:
First we convert the given reactant masses into moles, using their respective molar masses:
- 4.00 g H₂ ÷ 2 g/mol = 2 mol H₂
- 6.20 g P₄ ÷ 124 g/mol = 0.05 mol P₄
0.05 moles of P₄ would react completely with (6*0.05) 0.3 moles of H₂. There are more H₂ moles than required, meaning H₂ is in excess and P₄ is the limiting reactant.
Now we<u> calculate how many PH₃ moles could be formed</u>, using the <em>number of moles of the limiting reactant</em>:
- 0.05 mol P₄ *
= 0.2 mol PH₃
Finally we <u>convert 0.2 mol PH₃ into grams</u>, using its <em>molar mass</em>:
- 0.2 mol PH₃ * 34 g/mol = 6.8 g
So the correct answer is option D.
Answer:
b. decreases
C. neither a physical change nor a chemical change
light work
Answer:
<em>C. Potential energy</em>
Explanation:
Kinetic energy and gravitational potential energy are both forms of potential energy. Potential energy is stored energy, when an object is not in motion it has stored energy. When an object is an motion it has kinetic energy. An object posses gravitational potential energy when it is above or below the zero height.