Answer:
1. B, D,
2.A, F
Explanation:
1. According to the law of conservation of mass, In a course of chemical reaction, matter can neither be created nor destroyed but can be changed from one form to another. This means the amount of matter at the begining and ending of a reaction must be thesame.
2. Chemical reaction is not easily reversible. when gas is produced, provided the reaction system is an open system, the gas cannot be recovered and the reactants cannot be recovered from the products. likewise color change are attributed to chemical reaction
Answer:
A strip of magnesium metal is ignited using a lighter wand. The result is
an intensely glowing white light. As the burning of the metal subsides, a
white powder-like substance now appears replacing the smooth ribbon of
metal.
Answer: 55
Explanation: A atom consists of a nucleus and electrons.Nucleus contain neutrons with no charge and protons with positive charge. The electrons bearing negative charge revolve around the nucleus.
An electrically neutral atom contains equal number of protons and electrons. Thus if a neutral element X contains 55 protons, it also contains 55 electrons.
Answer:
The answer to your question is 6
Explanation:
Data
Cu + 2AgNO₃ ⇒
To find the answer, count the number of each element in the reactants
Element Quantity
Copper 1
Silver 2
Nitrogen 1
Oxygen 6
Then, in the products, there must be 6 oxygens so in the products there must be 6 oxygens so the reaction is balanced.
Atmospheric pressure decreases because air is less dense at higher altitudes. Because the atmospheric pressure is lower, the vapour pressure of the liquid needs to be lower to reach boiling point.
