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.
It’s easy, if the PH of any acidic solution = -Log[H+], where [H+] is hydrogen ion concentration, multiply each term by (-1) then raise each term as a power to (10), so it will become like this:-
[H+] = 10^(-PH)
Explanation:
Z = atomic mass of the element and , A = atomic mass of the element .
a) Z = 11, A = 23
Element = Sodium
symbol: ²³₁₁Na .
b) Z = 28, A = 64
Element = Nickel
symbol: ⁶⁴₂₈Ni .
c) Z = 50, A = 115
Element = tin
symbol: ¹¹⁵₅₀Sn .
d) Z = 20, A = 42
Element = Calcium
symbol: ⁴²₂₀Ca .
Zinc is no longer the positive electrode because copper has a more positive (higher) value than zinc (anode). The anode value is reduced by the potential of the other electrode.
<h3>In a galvanic cell, is the anode positive or negative?</h3>
In a galvanic (voltaic) cell, the cathode is regarded as positive and the anode as negative. This seems reasonable given that the cathode is where electrons flow from the anode, which is where they originate.
<h3>What is a galvanic cell?</h3>
An electrochemical cell called a galvanic cell or voltaic cell, respectively named after the scientists Luigi Galvani and Alessandro Volta produces an electric current by spontaneous oxidation-reduction reactions. A typical device typically consists of two distinct metals that are submerged in separate beakers that each contains their own metal ions in solution and are either connected by a salt bridge or divided by a porous membrane.
Learn more about Galvanic cells here:-
brainly.com/question/13927063
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