Answer:
<h3>Right answer is: ( a) chalk powder remains suspended in water.</h3>
Explanation:
Filtration is the technique used to separate suspended solute particles from a solution . The chalk powder remains suspended in the solution and can easily be filtered through a filter paper , the chalk powder can be collected on the filter paper and clear solvent is collected as the filtrate.
Answer:
The answer is option a. The evaporation of water from the skin
Explanation:
An endothermic reaction is any synthetic reaction that retains heat from its environment. The ingested energy gives the enactment energy to the reaction to happen.
No new bonds formed, no bonds broken in this example. water molecules go from liquid to vapour (gas ), intermolecular bond exist between polar (-OH) molecules and energy is required to break these bonds during the change from liquid to gas. So, it is endothermic .
Remaining three above examples are exothermic. combustion of gas releases energy(exothermic). burninig of the candle exothermic because the energy released from the oxygen into carbon dioxide and water.oxidation of iron also exothermic
H• •Be• •H --> H:Be:H
Since there are 4 valence electrons in total, Beryllium has 2 and Hydrogen has 2. You would put the Be in the middle because there is only 1 of them.
Answer:
N2O5
Explanation:
IUPAC ID: Dinitrogen pentoxide
Molar mass: 108.01 g/mol
Density: 1.64 g/cm³
Answer:
Explanation:
Given parameters :
Volume of solution = 100mL
Absorbance of solution = 0.30
Unknown:
Concentration of CuSO₄ in the solution = ?
Solution:
There is relationship between the absorbance and concentration of a solution. They are directly proportional to one another.
A graph of absorbance against concentration gives a value of 0.15M at an absorbance of 0.30.
The concentration is 0.15M
Also, we can use: Beer-Lambert's law;
A = ε mC l
where εm is the molar extinction coefficient
C is the concentration
l is the path length
Since the εm is not given and assuming path length is 1;
Then we solve for the concentration.
