Answer:
Explanation:
Given :
Mass of a bar of lead = 115.2 g
Initial water level 
= 25 mL
Final water level = 35.5 mL
Difference in the water level = 35.5 - 25
= 10.5 mL
= 
We know that when a body is submerged in water, it displaces its own volume of water.
Therefore, the volume of the lead bar = volume of the water displaced = 10.5 mL =
We know that mathematically, density is the ratio of mass of body to its volume.
Density of the lead bar is given by :
=
Answer:
Actual yield = 86.5g
Explanation:
Percent yield = 82.38%
Theoretical yield = 105g
Actual yield = x
Equation of reaction,
CaCO₃ + HCl → CaCl₂ + CO₂ + H₂O
Percentage yield = (actual yield / theoretical yield) * 100
82.38% = actual yield / theoretical yield
82.38 / 100 = x / 105
Cross multiply and make x the subject of formula
X = (105 * 82.38) / 100
X = 86.499g
X = 86.5g
Actual yield of CaCl₂ is 86.5g
True.
<span><span>Melting points decrease down a group and increase across a period.</span>
</span>
"One has more oxygen atoms than the other" best distinguishes carbon dioxide from carbon monoxide
<u>Explanation</u>:
In both carbon monoxide and carbon dioxide, there is the presence of carbon and oxygen. However,they vary depending on the number of oxygen atoms.In carbon monoxide, there is the presence of one only carbon and oxygen atom. Thus carbon monoxide is chemically represented as CO. Only about 0.2%ppm of carbon monoxide present in air. carbon monoxide is toxic and causes death in human when not consumed is correct proportion.
Whereas in carbon dioxide, only one carbon atom,and two oxygen atom and hence chemically represented as co2.
Answer:
0.34 M
Explanation:
I assume that the compound is PbCl2.
One mole of PbCl2 contains one mol of Pb+2 and 2 moles of Cl-
Molarity (M)= moles (n) /Volume (V)
Moles Pb2+ = M x V = 0.17 V
Moles Cl- = moles Pb2+ x (2 moles Cl-/1 mole Pb2+) = 0.17 V x 2 = 0.34 V
M Cl- = moles Cl-/V = 0.34V/V = 0.34 M
