Answer:
Almost everything in our surroundings represent chemical change
Explanation:
●Rusting of iron in presence of moisture and oxygen.
●Burning of wood.
●Milk becoming curd.
●Formation of caramel from sugar by heating.
●Baking of cookies and cakes.
●Cooking any food.
●Acid-base reaction.
●Digestion of food.
Answer:
S= 2(1) = 2
O= 2(4) = 8
Na= 2(2) = 4
Explanation:
The given compound is:
2Na₂SO₄
An element is a distinct substance that cannot be split up into simpler substances.
So;
Number of atoms of elements here are:
S= 2(1) = 2
O= 2(4) = 8
Na= 2(2) = 4
Answer :
(a) 0.0152
(b) 0.0000000778
(c) 0.000001
(d) 1600.1
Explanation :
Scientific notation : It is the representation of expressing the numbers that are too big or too small and are represented in the decimal form with one digit before the decimal point times 10 raise to the power.
For example :
5000 is written as 
889.9 is written as 
In this examples, 5000 and 889.9 are written in the standard notation and
and
are written in the scientific notation.
(a) 
The standard notation is, 0.0152
(b) 
The standard notation is, 0.0000000778
(c) 
The standard notation is, 0.000001
(d) 
The standard notation is, 1600.1
Either C or D. Those r the answers that make more sense.