Answer:
Explanation:
We have to make 100 mL 0f .405M HCl from 3 M solution of HCl .
volume of 3M to be taken required . Let this volume be V litre .
V litre of 3M will contain 3 V moles of HCl .
moles contained by 100 mL of ,405 HCl = .405 x .1 = .0405 moles .
So 3V = .0405
V = .0405 / 3 litre
= .0405 x 1000 / 4 mL
= 10.125 mL
So we have to take 10.125 mL of 3M HCl and add water to them to make its volume 100 mL .
Answer: Option (D) is the correct answer.
Explanation:
- A pure substance is defined as the substance that is made up of only one type of atom or only one type of molecule.
For example, 
is a molecule and it is a pure substance.
Also, substances that contain two or more different element which are chemically combined in a fixed ratio by mass are known as compounds. They are also pure substances.
A pure substance can only be separated by a chemical method and not by any physical method.
- A heterogeneous mixture is defined as the mixture which contains non-uniform composition of solute particles into the solution.
For example, mud dissolved in water.
It is not necessary that two or more substance present in a heterogeneous mixture should be of same phase.
Also, it is not necessary that combination of a liquid and a solid always results in a heterogeneous mixture.
If the solid is able to dissolve completely into the liquid then it will result in a homogeneous mixture.
- Whereas a homogeneous mixture is defined as the mixture which contains uniform distribution of solute particles into the solvent.
For example, salt dissolved in water is a homogeneous mixture.
Thus, we can conclude that the statement composition is uniform throughout a homogeneous mixture, is correct.
Answer:
16
Explanation:
Group two elements are alkaline earth metal.
All these have two valance electrons. In order to achieve noble gas configuration it loses its two valance and get complete octet.
Reaction with group 16.
Reaction with oxygen,
They react with oxygen and form oxide.
2Ba + O₂ → 2BaO
2Mg + O₂ → 2MgO
2Ca + O₂ → 2CaO
this oxide form hydroxide when react with water,
BaO + H₂O → Ba(OH)₂
MgO + H₂O → Mg(OH)₂
CaO + H₂O → Ca(OH)₂
With sulfur,
Mg + S → MgS
Ca + S → CaS
Ba + S → BaS
Answer:
- 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Explanation:
<em>Photosynthesis</em> is the chemical process carried out by plants for the conversion of inorganic matter (carbon dioxide and water) into organic matter (glucose) with the release of oxygen, using light (sun energy).
So the chemical process may be represented by:
carbon dioxide + water + sun energy → glucose + oxygen
- <u>Skeleton equation:</u>
CO₂ + H₂O + sun energy → C₆H₁₂O₆ + O₂
- <u>Balanced chemical equation:</u>
6CO₂ + 6H₂O + sun energy → C₆H₁₂O₆ + 6O₂
- <u>Supressing the energy to show only the chemical compounds:</u>
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Answer:
C. Hair dryer
Explanation:
Alternating Current
The other kind of electricity is called alternating current, or AC. Power plants produce this
type of electricity. It is carried by large power lines from the plant to your home. When you
plug a TV, a lamp, or a hair dryer into the wall socket, you are using this type of electricity.
