Answer:
chemical changes
Explanation:
A chemical change is one in which a new kind of matter is formed. It is always accompanied by energy changes. The process is not easily reversible and hence, it is a permanent procedure.
Burning of charcoal produces a new kind of produces in the combustion process.
Both heating of copper(ii)carbonate strongly and zinc oxide will lead to a decomposition reaction in which new compounds are formed.
Answer:
The answer to your question is given after the questions so I just explain how to get it.
Explanation:
a)
Get the molecular weight of Phosphoric acid
H₃PO₄ = (3 x 1) + (31 x 1) + (16 x 4)
= 3 + 31 + 64
= 98 g
98 g ----------------- 1 mol
0.045 g --------------- x
x = (0.045 x 1) / 98
x = 0.045 / 98
x = 0.00046 moles or 4.6 x 10 ⁻⁴
b)
Molarity =
Molarity =
Molarity = 0.0013 or 1.31 x 10⁻³
c)
Formula C₁V₁ = C₂V₂
V₁ = C₂V₂ / C₁
Substitution
V₁ = (0.0013)(1) / 0.01
Simplification and result
V₁ = 0.0013 / 0.1
V₁ = 0.13 l = 130 ml
Answer:
2.5g
Explanation:
When the reaction goes into completion, they will produce 2.5g. This is complement the law of conservation of mass.
According to the law of conservation of mass "in a chemical reaction, matter is neither created nor destroyed but transformed from one form to another".
- The mass of reactants and products in a chemical reaction must be the same.
- There is no change in mass in moving from reactant to product
- So, if we start with 2.5g of reactants, we must end with 2.5g of products.
The final volume V₂=4.962 L
<h3>Further explanation</h3>
Given
T₁=20 + 273 = 293 K
P₁= 1 atm
V₁ = 4 L
T₂=100+273 = 373 K
P₂=780 torr=1,02632 atm
Required
The final volume
Solution
Combined gas law :
P₁V₁/T₁=P₂V₂/T₂
Input the value :
V₂=(P₁V₁T₂)/(P₂T₁)
V₂=(1 x 4 x 373)/(1.02632 x 293)
V₂=4.962 L