Answer:
The value is 
Explanation:
From the question we are told that
The molar mass of
is 
The total mass is
The uncertainty of the total mass is 
Generally the molar weight of calcium is 
The percentage of calcium in calcite is mathematically represented as


Generally the mass of each sample is mathematically represented as



Generally mass of calcium present in a single sample is mathematically represented as


The uncertainty of mass of a single sample is mathematically represented as



The uncertainty of mass of calcium in a single sample is mathematically represent

Generally the average mass of calcium in each sample is

It would be c because it has to get hot so it is absorbing the heat not releasing it
Answer:physical: a part falling off or changing a tire. chemical:rust
Explanation:
Answer:
ΔGreaction < 0
ΔSuniverse > 0
ΔHreaction < 0
Explanation:
A spontaneous process is one which can proceed without additional input of energy releasing free energy in the process and then moves to a lower more stable thermodynamical state.
For an isolated system, a spontaneous process proceeds with an increase in entropy.
The conditions for a spontaneous process at constant temperature and pressure, can be determined using the change in Gibbs free energy, which is given by: ∆G = ∆H - T∆S
Where ∆G is change in free energy; ∆H is change in enthalpy or Heat content; ∆S is change in entropy, T is temperature.
For a process to be spontaneous, the following conditions are necessary:
1. ∆G < 0; must be negative
2. ∆S > 0; there must be an increase in entropy
3. ∆H < 0; enthalpy change must be negative such that heat is lost to the surroundings
The above conditions ensures that ∆G is negative and the process is spontaneous.