From google but i can explain further if needed. <span> The </span>balanced<span> equation for the reaction of interest contains the stoichiometric ratios of the reactants and products; these ratios </span>can<span> be used as </span>conversion factors<span> for mole-to-mole </span>conversions<span>.</span>
Answer:
Explanation:
Given that,
The dimensions of the board is 5.54 cm x 10.6 cm X 199 cm.
The mass of the board is 28.6 kg.
Since, 1 kg = 1000 grams
28.6 kg = 28.6 × 1000 g = 28600 grams
Density = mass/volume
So,
So, the density of a board is 
.
The original or accepted value for the percent by mass of water in a hydrate = 36%
Percen by mass of water in the hydrate determined by the student
in the laboratory = 37.8%
So the difference between the actual and the percent by mass in water determined by student = (37.8 - 36.0)%
= 1.8%
So the percentage of error made by the student = (1.8/36) * 100 percent
= (18/360) * 100 percent
= ( 1/20) * 100 percent
= 5 percent
So the student makes an error of 5%. Option "1" is the correct option.
