Answer:

Explanation:
We are given the volumes and concentrations of two reactants, so this is a limiting reactant problem.
We know that we will need moles, so, lets assemble all the data in one place.
Cu²⁺ + 4NH₃ ⟶ Cu(NH₃)₄²⁺
V/mL: 3.00 7.00
c/mol·L⁻¹: 0.050 0.20
1. Identify the limiting reactant
(a) Calculate the moles of each reactant

(b) Calculate the moles of Cu(NH₃)₄²⁺ that can be formed from each reactant
(i) From Cu²⁺

(ii) From NH₃

NH₃ is the limiting reactant, because it forms fewer moles of the complex ion.
(c) Concentration of the complex ion

Answer:
B). Precision.
Explanation:
During the course of measurements, two important factors are been seen to play key part which are accuracy and also precision. Precision here can reflect to the closeness of an answer towards the main value even though accuracy can show that too. Also it can show series of values been reproduced in the measurement flow; though in some cases can be a bit far from the actual value. Also its values are swen to be different because of repeatition and alsio in some cases, observational errors too.
We are given ΔG°rxn = -30.5 kJ/mol for the following reaction:
ATP + H₂O → ADP + HPO₄²⁻
We are given a series of concentrations for each of the species and are asked to find the value of ΔG for the reaction. We can use the following formula:
ΔGrxn = ΔG°rxn + RTlnQ
We can use R = 0.008314 kJ/molK; T = 335.15 K and Q is the reaction quotient which can be found as follows, and be sure to first convert each concentration of mM to M:
Q = [ADP][HPO₄²⁻]/[ATP]
Q= [0.00010][0.005]/[0.005]
Q = 0.0001
Now we can use the above formula to solve for ΔGrxn.
ΔGrxn = -30.5 kJ/mol + (0.008314)(310.15)ln(0.00010)
ΔGrxn = -54.3 kJ/mol
The value of ΔGrxn = -54.3 kJ/mol.