The specific heat capacity of this chunk of metal is equal to 0.32 J/g°C.
<u>Given the following data:</u>
- Quantity of energy = 400 Joules
- Initial temperature = 20°C
To determine the specific heat capacity of this chunk of metal:
<h3>
The formula for quantity of heat.</h3>
Mathematically, quantity of heat is given by the formula;

<u>Where:</u>
- Q represents the quantity of heat.
- m represents the mass of an object.
- c represents the specific heat capacity.
- ∅ represents the change in temperature.
Making c the subject of formula, we have:

Substituting the given parameters into the formula, we have;

Specific heat, c = 0.32 J/g°C.
Read more on specific heat here: brainly.com/question/2834175
Freezing point depression depends of the number of particles of the solute in the solution.
1)Pure water have highest freezing point. All other solutions with given solutes will have lower temperatures.
2) The more particles of the solute in the solution the lower freezing point is going to be.
<span>b. 1.0 m NaCl ( dissociates and give 2 mol ions (1 mol Na⁺ and 1 mol Cl⁻))
c. 1.0 m K3PO4 (</span>dissociates and give 4 mol ions (3 mol K⁺ and 1 mol PO4³⁻)<span>
d. 1.0 m CaCl2 (</span>dissociates and give 3 mol ions (1 mol Ca²⁺ and 2 mol Cl⁻))<span>
e. 1.0 m glucose (c6h12o6) (glucose does not dissociate, and solution have
1 mole of particles of the solute(glucose))
The largest number of particles has </span>1.0 m K3PO4 solution, and it is has lowest freezing point . Answer is C.
Given concentration of NaCl=15%
Means ,
In every 100g of Solution 15g of NaCl is present .
Now
So ,



<u>37.5g of NaCl present in 250g of solution.</u>
Combustion is a chemical reaction between a fuel and an oxidant, oxygen, to give off combustion products and heat. Complete combustion results when all of the fuel is consumed to form carbon dioxide and water, as in the case of a hydrocarbon fuel. Incomplete combustion results when insufficient oxygen reacts with the fuel, forming soot and carbon monoxide.
The complete combustion of propane proceeds through the following reaction:

+

-->

+

Combustion is an exothermic reaction, which means that it gives off heat as the reaction proceeds. For the complete combustion of propane, the heat of combustion is (-)2220 kJ/mole, where the minus sign indicates that the reaction is exothermic.
The molar mass of propane is 44.1 grams/mole. Using this value, the number of moles propane to be burned can be determined from the mass of propane given. Afterwards, this number of moles is multiplied by the heat of combustion to give the total heat produced from the reaction of the given mass of propane.
14.50 kg propane x <u> 1000 g </u> x <u> 1 mole propane </u> x <u> 2220 kJ </u>
1 kg 44.1 g 1 mole
=
729,931.97 kJ