Explanation:
A chemical reaction is defined as the reaction in which bonds between the reactants either break or form which leads to the formation of a new substance.
For example, 
So, when we drop a sodium metal into water then it produces a frizzing sound which shows the metal is reacting with water.
We know that when two aqueous solutions chemically react with each other then it may lead to the formation of an insoluble substance which is known as precipitate.
This means that formation of a precipitate is also a chemical reaction.
Thus, we can conclude that following are the statements which show evidence for a chemical reaction.
- Dropping sodium metal into water produces fizzing.
- Mixing two aqueous solutions produces a precipitate.
Answer:
Yes, Mass is conserved.
Explanation:
Every chemical reactions obey the law of conservation of mass. The law of conservation of mass states that in chemical reactions, mass is always constant.
Equation:
2Na + Cl₂ → 2NaCl
From the equation above, one can observe that the reaction started using 2 atoms of Na and it produced 2 atoms of the same element in NaCl. A molecule of Cl produced 2 atoms of Cl in the NaCl
Design a simple experiment to support your answer:
Aim: To demonstrate the law of conservation of mass
One Na atom weighs 23g
Two Na atom will weigh 2 x 23 = 46g
1 atom of Cl is 35.5g
1 molecule of Cl containing two atoms of Cl will weigh 2 x 35.5 = 71g
Total mass of reactants = mass of 2Na + 1Cl₂ = (46 + 71)g = 117g
On the product side, Mass of 1 NaCl = 23+ 35.5 = 58.5g
Two moles of NaCl will give 2 x 58.5g = 117g
Since the mass on both side is the same, one can say mass is conserved.
Answer:
No, Mercury can actually cause poisoning. That is why other metals, such as Alkaline metals, are used in making batteries
Answer:
5=C, every action has an equal or opposite reaction,
6=B, since it has less air drag and more force exerted on it
7= You're correct
