Evaporation technique is used to separate a compound dissolved in a solvent by vaporizing the solvent and converting it to gaseous state. This leaves behind the solid residue present in the solution after the pure solvent is vaporized. The solvent vapors can be collected and condensed to get pure solvent. But the solid residue cannot be considered pure as it is the left over solid after all the solvent is evaporated. If the solution has some impurities, the solid left over includes all of the impurities. So, we cannot obtain a pure solid in evaporation technique.
Answer:
Protons = 11
Electrons = 10
Neutrons = 12
Explanation:
The atomic number of an element is the number of protons present in the nucleus of an atom of that element. A neutral atom of an element contains equal number of protons and electrons, therefore, the atomic number is also the electron number for a neutral atom.
The mass number is the sum of proton and neutrons in the nucleus of an atom of an element.
The atomic number of sodium-23, Na-23 is 11 while the mass number is 23.
An atom of sodium that has a net charge of +1 has lost an electron. Therefore, from the above information, the number of protons, neutrons and electrons present in this atom of sodium-23 is as follows:
Protons = 11
Electrons = 11 - 1
Electrons = 10
Neutrons = 23 - 11
Neutrons = 12
Answer: Option (c) is the correct answer.
Explanation:
HF is a weak acid and not a strong acid. This is because fluorine is a highly electronegative atom and when it combines with a hydrogen atom then it will attract the valence electron of hydrogen atom more towards itself.
As a result, it will not dissociates easily to give hydrogen ion. Hence, it acts as a weak acid.
A neutralization reaction is defined as a reaction in which an acid reacts with a base to give salt and water. For example,
It is true that, spectator ions "appear in the total ionic equation for a reaction, but not in the net ionic equation".
Titration is defined as a process in which concentration of an unknown solution is determined using a solution of known concentration.
Thus, we can conclude that the statement HF, HCl, and HNO3 are all examples of strong acids, is false.
Answer:
False, we cannot made 16 muffins from 3 eggs.
Explanation:
2 cups flour + 1 egg + 3 oz blueberries → 4 muffins
According top recipe, 2 cups of flour, 1 egg and 3 oz of blueberries are made into batter to give 4 muffins.
Then 16 muffins will made from:
For each muffin we need =
Then for 16 muffins we will need:
4 eggs will be required to make 16 muffins
From 1 egg we can made 4 muffins
Then from 3 eggs we can made = 3 × 4 muffins = 12 muffins
12 muffins will made from 3 eggs.
We cannot make 16 muffins from 3 eggs.