Answer:
Option (2), (3) and (5).
Explanation:
Chemical change: It is a chemical reaction in which arrangement of atoms of one or more than one substance changes to give new substances as a product.Chemical change can be in form of : color change, formation of precipitate, formation of bubbles.
In option (2), bubbles were produced when iron was placed in acid which means gas was released on adding iron to acid.Yes, it is a chemical change.
In option (3), solid that is precipitate is obtained as a product from the reaction between two liquids which means that change in arrangement of atom had taken place.Hence, a chemical change.
In option (5), white substance turned blue when water was added. Color of white solid changes to blue which means that chemical change has taken place.
So, option are (2), (3) and (5) are examples of chemical changes.
Answer: 0 neutrons
Explanation:
to find neutrons you subtract the atomic number from the Atomic mass. The atomic mass is 1. The atomic number is 1. So 1-1=0 making the neutrons in a hydrogen molecule 0.
Answer:
Left or up, either one of those
Explanation:
Hey there!
2Na + Cl₂ → 2NaCl
This is a balanced chemical equation.
There are 2 atoms of sodium (Na) on the left, and 2 atoms of sodium (Na) on the right.
There are 2 atoms of chlorine (Cl) on the left, and 2 atoms of chlorine (Cl) on the right.
This means the equation is balanced since there are the same amount of each element on both sides.
Hope this helps!