Answer:
A
Explanation:
Opposite charges attract therefore the electrons of one atom would be attracted by the nucleus (which contains protons). This heavily relies on a property called electronegativity. Which deals with the level of attraction a nucleus (the protons in the nucleus) have for electrons of other atoms.
Answer:D. Ratio of oxygen/nitrogen
Explanation: the ratio will never change no matter the air pressure!
For answering for the question, there exists four choices:
1) Na+ + e- -------------- Na
2) Na --------Na+ + e-
3) Cl2 + 2e- ------------ Cl-
4) 2Cl- ---------Cl2 + 2e-
reduction half-reaction general formula is
oxidant + e - or + -------- Product
so in our case the answer is
1) Na+ + e- -------------- Na (exactly balanced)
Watt stands for power that is energy per unit time
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.
