Answer:
3 moles
Explanation:
SrCO3
Mass = 442.8g
Molar mass = (87.6 + 12 * [16*3]) = 147.6g/mol
Number of moles = mass / molar mass
Number of moles = 442.8 / 147.6
Number of moles = 3
Answer:
A polar molecule has both a partial positive and a partial negative. Since NaCl (sodium chloride) is made out of Na+ and Cl- ions, the positive and negative parts of the water will pull on these ions individually since positive attracts negative and negative attracts positive. This magnetic force causes the Na+ and the Cl- ions to be pulled apart.
Explanation:
Answer:
There are five evidences that tell whether a chemical change has occurred. These are change of color, change of odor, change in temperature or energy, formation of gas and formation of a precipitate.
Explanation:
Chemical Change- This is a type of chemical reaction which occurs when the properties of one or more atoms change and results into a<u> newly formed substance. </u>
Let's have a further discussion of the evidences.
1. Change of Color- Color change is caused by the combination of two or more substance with different molecular structures. A popular example of this is the Statue of the Liberty, which is made of copper plates. Due to the exposure of copper to elements like water, it changed color.
2. Change of Odor- This can be best presented with rotting food. During the rotting process, the food undergoes a chemical reaction. The result is a rotten smell.
3. Change in Temperature or Energy- An example of this is the burning of wood. Its change is considered non-reversible.
4. Formation of Gas- This can be best presented with the cake batter (the one being used to make cakes or pancakes). The batter rises which means it is forming gas. This is caused by the reaction of the baking soda and the acid.
5. Formation of a Precipitate- This occurs when two soluble salts combine and their outcome is an insoluble salt (this is the precipitate).
Take note that if any of these evidences occur, then there's definitely a chemical reaction.
Answer:
Explanation:
From the information given:
Mass of carbon tetrachloride = 5 kg
Pressure = 1 bar
The given density for carbon tetrachloride = 1590 kg/m³
The specific heat of carbon tetrachloride = 0.84 kJ/kg K
From the composition, the initial volume of carbon tetrachloride will be:
= 0.0031 m³
Suppose 
is independent of temperature while pressure is constant;
Then:
The change in volume can be expressed as:
However; the workdone = -PdV
W = - 7.6 J
The heat energy Q = Δ h
Q = 84 kJ
The internal energy is calculated by using the 1st law of thermodynamics; which can be expressed as;
ΔU = ΔQ + W
ΔU = 84 kJ + ( -7.6 × 10⁻³ kJ)
ΔU = 83.992 kJ
The amount of molecules assembled, the processes performed on the substances. I'm not exactly sure of the question to be honest, but there's a start
