Answer:
I) Change in solubility
II) Change in boiling point
III) Change in colour
Explanation:
A chemical change involves formation of new products and is not reversible.
So, once two liquid solutions are mixed and a chemical change takes place, the new product will have the following:
- a new solubility rate, i.e it will dissolve at a rate different from the two liquid solution
- a new boiling point i.e it takes a new point at which its molecules liberate to yield vapour
- a new colour might be detected, as the individual solution each has its own colour
Answer:
option A= Physical change
Explanation:
physical change:
" It is a change in which no new substance is formed"
Breaking of object like glass is the example of physical change because it is not change into another object. It effect the form of object but can not change the chemical composition.
Chemical changes:
" it is a change in which one substance is converted into new product through chemical reaction".
During the chemical changes the types and the number of atom remain same but their arrangement changed.
for example: burning of wood, baking of cake, digesting food, resting of iron etc.
Physical reaction:
" physical reaction occur during the molecular rearrangement. There is no chemical change occur"
In this type of changes no bonds are break to form new bonds, for example boiling point.
Chemical reaction:
" chemical reaction occur when molecules are chemically react with each others and bonds formation and breaking is also occur"
Answer:
Yes. The two elements can combine to form different compounds.
Explanation:
Two elements can combine at different ratios.
Consider CO and CO₂. Both are made from carbon and oxygen. However, C and O combine at a 1:1 ratio in CO but at a 1:2 ratio in CO₂. CO is a fuel; it burns in the air. CO₂ does not burn in the air; it is used to put out fires and is found in extinguishers. CO and CO₂ are two distinct compounds.
There are many ways for the elements to combine with each other. As a result, the first twenty elements on the periodic table alone can produce a large number of compounds.
Answer:
The minimum concentration of Cl⁻ that produces precipitation is 12.6M
Explanation:
The Ksp of PbCl₂ is expressed as:
PbCl₂(s) → Pb²⁺(aq) + 2Cl⁻(aq)
The Ksp is:
Ksp = 1.6 = [Pb²⁺] [Cl⁻]²
When Ksp = [Pb²⁺] [Cl⁻]² the solution begind precipiration.
A 0.010M Pb(NO₃)₂ is 0.010M Pb²⁺, thus:
1.6 = [0.010M] [Cl⁻]²
160 = [Cl⁻]²
12.6M = [Cl⁻]
<h3>The minimum concentration of Cl⁻ that produces precipitation is 12.6M</h3>
