Answer:
C)
Explanation:
M1V1 = M2V2
40.0ml*0.25M = M2*50.0ml
M2 = 40.0*0.25/50.0 = 0.20 M
Answer would be A. Why because isolation means that nothing can move in or out
Answer:
The steps that must be long to obtain separately the components (to the substances) of a mixture of water, salt and sand, are respectively: A) filtration and siphoning B) decanting and siphoning C) simple filtration and distillation D) collection and decantation.
Simple filtration and Siphoning is the method. When an insoluble solid is present in a liquid. Filtration is the ideal method of separation,The sand is filtered by the filtered paper as water is allowed to pass through the filter paper into a beaker where the funnel which hold the filter paper emptied into.
Water molecules is Siphoned, pull by force of gravity through the sand, past the filter paper to emerge as clean in the beaker below.
Answer:
73.4% is the percent yield
Explanation:
2KClO₃ → 2KCl + 3O₂
This is a decomposition reaction, where 2 moles of potassium chlorate decompose to 2 moles of potassium chloride and 3 moles of oxygen.
We determine the moles of salt: 400 g . 1. mol /122.5g= 3.26 moles of KClO₃
In the theoretical yield of the reaction we say:
2 moles of potassium chlorate can produce 3 moles of oxygen
Therefore, 3.26 moles of salt, may produce (3.26 . 3) /2 = 4.89 moles of O₂
The mass of produced oxygen is: 4.89 mol . 32 g /1mol = 156.6g
But, we have produced 115 g. Let's determine the percent yield of reaction
Percent yield = (Produced yield/Theoretical yield) . 100
(115g / 156.6g) . 100 = 73.4 %
