Answer:
Explanation:
<u>1) Data:</u>
a) m = 18 kg
b) T₁ = 285 K
c) T₂ = 318 K
d) Q = 267.3 kJ
e) S = ?
<u>2) Principles and equations</u>
The specific heat of a substance is the amount of heat energy absorbed to increase the temperature of certain amount (gram, kg, or moles, depending on the definition or units) of the substance in 1 ° C or 1 K.
The mathematical relation between the specific heat and the heat energy absorbed is:
Where,
- Q is the heat absorbed,
- S is the specific heat, and
- ΔT is the temperature increase (T₂ - T₁)
<u>3) Solution:</u>
<u>a) Substitute the data into the equation:</u>
- 267.3 kJ = 18 kg × S × (318 K - 285 K)
<u>b) Solve for S and compute:</u>
- S = 267.3 kJ / (18 kg × 33 K) = 0.45 kJ / (Kg . K)
The options have not units, but I notice that the first answer is 1,000 times the answer I obtained, so I will make a conversion of units.
<u>c) Convert to J /( kg . k):</u>
- 0.45 kJ / (Kg . K) × 1,000 J / kJ = 450 J / (kg . K)
Now we can see that the option A is is the answer, assuming the units.
Answer:
A chemical formula for a molecular compound represents the composition of <u><em>a molecule.</em></u>
Explanation:
Chemical formulas are alphanumeric expressions that are used to indicate the composition of chemical substances. They consist of chemical symbols that indicate the elements that form a compound; The number of atoms provided by each element is also indicated by the use of a subscript, that is, a small number that is placed below and to the right of each element that so requires. When an element does not have a subscript, it is understood that there is only one atom of it in the substance.
Each molecule corresponds to a chemical formula, as well as a name according to the rules of the chemical nomenclature.
Then, <u><em>a chemical formula for a molecular compound represents the composition of a molecule.</em></u>
Boiling or also called evaporation is the conversion of liquid to gas through the application of heat. This phase change is an endothermic change and is the opposite of condensation from gas to liquid.
Space -filling models are also known as Calotte models. These are 3 dimensional models that depict the spatial relationships between atoms.
The space-filling model of water molecule shows the 3 D structure of the water molecule. This model CLEARLY REVEALS THE OXYGEN ATOM WHICH IS LOCATED CENTRALLY WITH TWO HYDROGEN ATOMS IN THE ADJACENT SIDES. THE MODEL ALSO SUGGESTS HOW THE WATER MOLECULES ATTRACT EACH OTHER.
