Answer:
33.58%
Explanation:
Data obtained from the question include:
Mass of CuS = 9.56g
Mass of Cu = 6.35g
Mass of S = Mass of CuS — Mass and Cu
Mass of S = 9.56 — 6.35
Mass of S = 3.21g
The percentage by mass of sulphur in CuS is given by:
Mass of S/mass of CuS x 100
Percentage by mass of S = 3.21/9.56 x 100 = 33.58%
Answer:
The correct option is desertification
Explanation:
Deforestation is the deliberate act of pulling down trees to provide a clear land for space or to make use of the trees for other purposes such as grazing, farming, timber fire wood, building and constructions, urban utilization, access roads, expansion, development of infrastructures, grazing of cattle and mining
The effects of deforestation includes climate change, flooding, increase in the proportion of green house gases in the atmosphere, soil erosion and desertification.
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The balanced chemical reaction would be
<span>fecl2 + 2naoh = fe(oh)2(s) + 2nacl
Initial amounts of the reactants are given, so, we need to determine which of the reactants is the limiting reactant and use this amount to determine what is asked. However, what is being asked is how many of the FeCl2 is used in the reaction, showing that it is NaOH that is the limiting reactants. Thus, we just use the initial amount of NaOH and relate the substances by the chemical reaction as follows:
6 mol NaOH ( 1 mol FeCl2 / 2 mol NaOH ) = 3 mol FeCl2
Therefore, 3 moles of FeCl2 is used up and 3 moles of FeCl2 is also left after the reaction.</span>