Q1)
the number of moles can be calculated as follows
number of moles = mass present / molar mass
number of moles is the amount of substance.
4.8 g of Ca was added therefore mass present of Ca is 4.8 g
molar mass of Ca is 40 g/mol
molar mass is the mass of 1 mol of Ca
therefore if we substitute these values in the equation
number of moles of Ca = 4.8 g / 40 g/mol = 0.12 mol
0.12 mol of Ca is present
q2)
next we are asked to calculate the number of moles of water present
again we can use the same equation to find the number of moles of water
number of moles = mass present / molar mass
3.6 g of water is present
sum of the products of the molar masses of the individual elements by the number of atoms
H - 1 g/mol and O - 16 g/mol
molar mass of water = (1 g/mol x 2 ) + 16 g/mol = 18 g/mol
molar mass of H₂O is 18 g/mol
therefore number of moles of water = 3.6 g / 18 g/mol = 0.2 mol
0.2 mol of water is present
Answer:
The correct answer is option A.
Explanation:
Volumetric flask : A glass ware with round lower body with flat bottom and with thin cylindrical neck along with mark which indicates the specific volume filled to that mark.It is used in preparation of standard solution of compound with desired concentration with fixed volume.
Erlenmeyer flask
: is a flask with conical shape with flat bottom used in titration experiments to carry out reaction with fixed volume of solution.
Test tube
: Small cylindrical tube with rounded bottom used to observe reaction in between reactant taken in small amount.
Graduated beaker
: Laboratory glassware used measure larger volumes of solution or to mix or stir solutions and liquids.
Graduated cylinder : Laboratory thin cylindrical glassware with accurate marking of volume used to measure an accurate volume of solutions or liquids required in an experiment.
<em><u>Volumetric flask</u></em> is the best piece of laboratory glassware for preparing 500.0 mL of an aqueous solution of a solid
Hey there! The answer to your first question is SILICON, Nickle has 28 protons, silicon has 14, 14+14=28. Its the only element thats adds up. I dont know about the 2nd one myself.
PH of solution will be greater than seven (pH>7), that means that solution is basic (<span>pH above </span>7<span> is a base, the higher the number, the stronger is the base).
</span>pH (potential of hydrogenis) is a measure of the hydrogen ion (H⁺) concentration of a solution. <span>Solutions with a pH less than 7 are acidic.</span>
Answer:
the candle is still solid..................in this case, yes!
Explanation:
it is still solid because the molecules are packed together tighter than the molecules in a liquid or gas.
