4 is correct. Since gases are made of rapidly moving molecules with a relatively high amount of kinetic energy, the molecules have a hard time coming together to form a liquid. You must lower their kinetic energy with a low temperature and force the molecules together with high pressure.
Answer:
The order of some common metals in the electromotive series, starting with the most easily oxidized, is: lithium, potassium, calcium, sodium, magnesium, aluminum, zinc, chromium, iron, cobalt, nickel, lead, hydrogen, copper, mercury, silver, platinum, and gold.
Explanation:
Answer:
Option A, The pH of the solution is 2.7 and the solution is acidic
Explanation:
As we know,
pH = - log [H3O+]
Substituting the given values, we get
pH = - log [2.1 x 10-3 M]
pH = - (-2.678)
pH = 2.678 or 2.7
The solution is acidic as pH value is less than 7
Hence, option A is correct
<h3>
Answer:</h3>
0.144 moles
<h3>
Explanation:</h3>
- The relationship between mass of a compound, number of moles and molar mass of the compound is given by;
- Number of moles = Mass ÷ Molar mass
- Molar mass is equivalent to the relative formula mass of the compound that is calculated the atomic masses of the elements making the compound.
In this case;
Our compound, KClO3 will have a molar mass of;
= 39 + 35.5 + 4(16)
= 138.5 g/mol
Mass of KClO3 is 20 g
Therefore;
Number of moles = 20 g ÷ 138.5 g/mol
= 0.144 moles
Thus, the number of moles in 20 g of KClO3 is 0.144 moles
