To develop the chemical formula of a substance or compound in this regard, one only needs to write the chemical symbol for each of the element present and write as subscript to each symbol the number of atoms of that element. For nitrobenzene, as described above, the chemical formula should be,
C₆H₅O₂N
Answer:
True
Explanation:
The physical and chemical properties of a substance depend on the nature of intermolecular forces between its molecules. For instance, water has a high boiling point because of hydrogen bonding between water molecules. Liquid water is denser than ice because of the difference in the nature of hydrogen bonding in liquid water and ice.
In 1871, a Russian Chemist, Dimitri Mendeleev, gave a useful scheme for classification of elements. He presented the first regular periodic table in which elements of similar chemical properties were arranged in eight vertical columns called groups. The horizontal rows of table were called periods. He arranged elements in ascending order of their atomic masses and found that elements having similar chemical properties appeared at regular intervals. This observation was called Periodic Law.
I know for number 4 the answer is c, sorry I can't help with the others.
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