Answer: You need a control group because......
Explanation: You need a control group in order to study if there is any difference in behavior between two groups when an external stimulant is introduced.
The fire decreases since fire needs oxygen in order to burn
Answer:
1. London dispersion
Explanation:
Sulphur trioxide ( SO₃ ) -
The chemical compound SO₃ is planar in structure , the only intermolecular forces shown by SO₃ is the London forces .
dipole - dipole is not observed in this compound , as it is not possible to generate poles between the sulfur and oxygen atom due to very less difference in the electronegativity .
Hydrogen bonding is also not observed , because there is not hydrogen atom .
Hence , only London forces are observed in SO₃ .
Answer:
20.67 kcal of energy is released.
Explanation:
It is given that, an exothermic reaction releases 86.5 kJ. We need to convet kJ to calories.
Since,
1 kcal = 4.184 kJ
So,
1 kJ = 0.239 kcal
For 86.5 kJ,
86.5 kJ = (0.239 × 86.5) kcal
86.5 kJ = 20.67 kcal
So, 20.67 kcal of energy is released.