Answer:
17.76g
Explanation:
We need to write a balanced chemical equation for the reaction:
2Al(OH)3 + 3Ca(NO3)2 ——> 3Ca(OH)2 + 2Al(NO3)3
In the reaction above, it can be seen that 2 moles of aluminum hydroxide yielded 3 moles of calcium hydroxide. This is the theoretical viewpoint.
Now we need to know what actually happened. We need to calculate the actual number of moles of aluminum hydroxide reacted l. We can get this by dividing the mass by the molar mass.
The molar mass of aluminum hydroxide is 27+ 3( 16+1)
= 27 + 51 = 78g/mol
The number of moles is thus: 12.55/78 = 0.16 moles
Now if 2 moles of aluminum hydroxide gave 3 moles of calcium hydroxide, 0.16moles will give : (0.16*3)/2 = 0.24moles
Now we can calculate the mass of calcium hydroxide formed. The mass of calcium hydroxide formed is the number of moles multiplied by the molar mass.
The molar mass of calcium hydroxide is; 40 + 2(17) = 74g/mol
The mass is thus =74 * 0.24 = 17.76g
Answer:
The independent variable (IV) is the characteristic of a psychology experiment that is manipulated or changed by researchers, not by other variables in the experiment.
For example, in an experiment about the effect of nutrients on crop growth: The independent variable is the amount of nutrients added to the crop field. The dependent variable is the biomass of the crops at harvest time.
Therefore : 3. the variable that responds to what the scientist changes in an experiment
Answer:
Respiration might occur in the presence and absence of oxygen known as the aerobic respiration and anaerobic respiration. The ATP molecules are produced more in number in aerobic respiration.
The yeast has the ability to undergo the process of anaerobic respiration and its end product are alcohol, carbon dioxide and 2 moles of ATP. The yeast is grown on maltose medium but unable to produce alcohol because of the presence of oxygen in the medium. The oxygen might acts as poison or inhibit the process of anaerobic respiration.
Answer:
0.312 moles of H2O
Explanation:
no. of moles of ch4= mass ÷ molar mass
=2.5 ÷ 16.04
=0.156 moles of ch4
According to balanced chemical equation
CH4 : H2O
1 mole : 2 moles
0.156 moles : x moles
by cross multiplication
x= (0.156x2) ÷ 1
= 0.312 moles of H2O
There are a total of 4 elements
