The plants without any fertiliser could be the control, to see what the change in the independent variable (fertiliser) does to the growth of the plant (dependant variable).
Hope that helps.
Answer:
Atomic mass of E is 128.24
Explanation:
- The percentage composition by mass of an element in a compound is given by dividing the mass of the element by the total mass of the compound and expressing it as a percentage.
- In this case; the compound Bi₂E₃
Percentage composition of bismuth = 52.07%
Percentage composition of E = 47.93%
Mass Bismuth in the compound is (2×208.9804) = 417.96 g
Therefore,
To calculate the atomic mass of E
52.07% = 417.96 g
47.93% = ?
= (47.93 × 417.96 ) ÷ 52.07 %
= 384.729
E₃ = 384.729
Therefore; E = 384.729 ÷ 3
= 128.24
The atomic mass of E is 128.24
Answer: (B) a strong acid
Explanation:
Acids turn blue pH paper red
the answer is c) a mixture that scatters light.