Please help with these questions ASAP will give brainlist!! CHEMISTRY


1.) A sample of nickel is heated to 95.0°C and placed in a coffee-cup calorimeter. If the 50.0 g of water in the calorimeter is initially 22.3°C and warms to 25.4°C, what mass of nickel was heated? (The specific heat of nickel is 0.444 J/°C g and water is 4.18 J/°C g.)


21.0 g



15.4 g



2.1 g



57.5 g


2.)What is the entropy change associated with the chemical reaction that occurs when iron oxide is converted to its metal form?

Fe2O3(s) + 3CO(g) → 2Fe(s) + 3CO2(g)


Positive



Zero



Cannot be determined



Negative


3.)The ΔH of the reaction below is -575.13 kJ. Is this reaction spontaneous?

2ZnS + 3O2 + C → 2SO2 + 2Zn + CO2


It is not because the ΔH of the reaction is negative.



It is because the ΔH of the reaction is negative.



It depends on the temperature because the ΔH of the reaction is negative and the ΔS is negative.



It depends on the temperature because the ΔH of the reaction is negative and the ΔS is positive.


4.) In the cell, the hydrolysis of ATP (adenosine triphosphate) into ADP (adenosine diphosphate) and a phosphate group has a ΔG of -50 kJ/mol. The reaction to convert glucose and a phosphate group into glucose-6-phosphate has a positive ΔG, but can be coupled with ATP hydrolysis to produce a spontaneous reaction. What can you infer about the formation of glucose-6-phosphate?

ATP → ADP + P; ΔG = -50 kJ/mol

Glucose + P → Glucose-6-phosphate; ΔG = + ?


The ΔS of the reaction that converts glucose and a phosphate into glucose-6-phosphate is positive.



The ΔG of the reaction that converts glucose and a phosphate into glucose-6-phosphate has a ΔG between 0 and +50 kJ/mol.



The ΔG of the reaction that converts glucose and a phosphate into glucose-6-phosphate has a ΔG between 0 and -50 kJ/mol.



The reaction will never occur in the cell.