Answer:
C) Chemical changes involve formation of a new substance while physical change only impacts appearance or form.
Explanation:
The obvious difference between a chemical change and physical change is that in a chemical change new substances are produced while in a physical change, the form of the compounds are altered.
- Most phase changes are products of physical changes. Such changes are easily reversible.
- In a chemical change, a new kind of matter is formed. It is accompanied by energy changes.
- The process is not easily reversible.
Answer:
Cấu hình điện tử của nguyên tố X là:
1s² 2s² 2p6 3s2 3p5
The electronic configuration of an element X is:
1s² 2s² 2p6 3s2 3p5
Answer:
Option A and C
Explanation:
Generally yield of wheat and rice crop is measured in terms of hundredweight. It is also known as centum weight or quintal. one quintal is equal to 100 Kg. It is used primarily in United States of America and British reign. In India quintal is used to measure the yield of wheat and rice
Hence, option A and C is the correct answer
