Answer:
111.68 g
Explanation:
Given data:
Mass of HgS needed = ?
Mass of CaS produced = 26.0 g
Solution:
Chemical equation;
4HgS + 4CaO → 4Hg + 3CaS + CaSO₄
Number of moles of CaS:
Number of moles = mass/molar mass
Number of moles = 26 g/ 72.143 g/mol
Number of moles = 0.36 mol
Now we will compare the moles of HgS with CaS.
CaS : HgS
3 : 4
0.36 : 4/3×0.36 = 0.48 mol
Mass of HgS:
Mass = number of moles × molar mass
Mass = 0.48 mol × 232.66 g/mol
Mass = 111.68 g
Answer: (a) There are 0.428 moles present in 12 g of 
molecule.
(b) There are 2 moles present in 
particles of oxygen.
Explanation:
(a). The mass of nitrogen molecule is given as 12 g.
As the molar mass of is 28 g/mol so its number of moles are calculated as follows.
So, there are 0.428 moles present in 12 g of molecule.
(b). According to the mole concept, 1 mole of every substance contains 
atoms.
Therefore, moles present in particles are calculated as follows.
So, there are 2 moles present in particles of oxygen.
Answer:
In technical astronomical terms, the equinox is the moment at which the sun appears to cross the equator as a result of Earth’ s rotation around the sun. The vernal (spring) equinox, which occurs as the sun moves from south to north across the equator, takes place around March 21 and marks the beginning of spring.
Explanation:
Answer:
HCl=18.7g.
Explanation: First, we ensure that the equation is balanced. Then, we convert the given grams to moles of reactant.
