C2H2 is the right answer I believe
Answer:
D, if the cliff is higher than the refrigerator
Explanation:
Answer:
pH of HNO₃ having an hydrogen ion concentration of 0.71M is 0.149
Explanation:
HNO₃ (aqueous) ⇄ H⁺ + NO3⁻
The pH is defined as the negative log of the hydrogen ion concentration
pH = - log [H⁺]
From the question, the hydrogen ion concentration is given as 0.71M, therefore
pH = -log [0.71]
= 0.149
Answer:
d) cut the large sized Cu solid into smaller sized pieces
Explanation:
The aim of the question is to select the right condition for that would increases the rate of the reaction.
a) use a large sized piece of the solid Cu
This option is wrong. Reducing the surface area decreases the reaction rate.
b) lower the initial temperature below 25 °C for the liquid reactant, HNO3
Hugher temperatures leads to faster reactions hence this option is wrong.
c) use a 0.5 M HNO3 instead of 2.0 M HNO3
Higher concentration leads to increased rate of reaction. Hence this option is wrong.
d) cut the large sized Cu solid into smaller sized pieces
This leads to an increased surface area of the reactants, which leads to an increased rate of the reaction. This is the correct option.
Answer:
The atmosphere traps heat energy from the Sun and energy radiated from Earth's surface helping to maintain Earth's climate
Explanation:
Earth's atmosphere keeps much of the Sun's energy from escaping into space. This process, called the greenhouse effect, keeps the planet warm enough for life to exist. The atmosphere allows about half of the Sun's heat energy (50%) to reach Earth's surface.
