The answer is A, a new chemical substance has to be formed for there to be a chemical change. This is because chemical change happens when a phase of matter changes due to chemicals.
Answer: Odor of ammonia would we detect first on the other side of the room.
Explanation:
To calculate the rate of diffusion of gas, we use Graham's Law.
This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:
Thus the odor of ammonia would we detect first on the other side of the room as the rate of effusion of ammonia would be faster as it has low molecular weight as compared to hydrogen sulphide.
A student tested a 0.1 M aqueous solution and made the
following observations conducts electricity, turns blue litmus to red and reacts
with Zn(s) to produce gas bubbles. The compound that could be the solute in
this solution is HBr. The answer is number 3.
Answer:
Zn(s) + 2H+(aq) => Zn²+(aq) + H2 (g)
Explanation:
The equation Zn + 2 HCI -> H₂ +zncl2 on reduction and oxidation, it results as below;
- 2H+ + 2e- => H2 ; reduction
- Zn => Zn²+ + 2e- ; oxidation
The equations above are half cell.
On combination of the above half cell reaction equations gives;
Zn(s) + 2H+(aq) => Zn²+(aq) + H2 (g).
Therefore, the half reaction equation for Zn + 2 HCI -> H₂ +zncl2 is given by;
Zn(s) + 2H+(aq) => Zn²+(aq) + H2 (g).
Newtown third law of motion says : when two objects interact , the forces they exert on each other are equal and opposite .
