<u>Answer:</u>
<em>The percentage error in the measurement is 2.4%
</em>
<u>Explanation:</u>
The measurement made by the student is
.
But the actual value of density is
The formula to calculate percentage error is
percentage error = 
Hence percentage error in this case is given by
<em>Percentage error =
</em>
<em>=
</em>
A physical quantities value will be determines by various quantities. If errors are made in measuring any of these quantities there will be error in the measurement of the final physical quantity as well.
Here density of a substance is a derived quantity determined by measuring mass and volume of that substance.<em> If errors are made in mass and volume measurements the density value will also be erroneous.
</em>
1.)1mps
2)no the slope starts to become steady
3.)there is no motion it stops
Density= 1.2092 because density = mass/volume
<span>1) </span><span>Deduce
the two masses and see the amount of water was driven off when heated: </span><span>
<span>5.03 g -
4.23 g = 0.8 g H2O given off </span>
<span>2) Change
mass from grams to moles of H2O: </span>
<span>0.8 g H2O
/ 18 g H2O in 1 mole = 0.044 mol H2O </span>
<span>3) Change
left over mass to moles of BaCl2 .</span></span>
<span>
<span>4.23 g
BaCl2 / 207 g BaCl2 in 1 mol = 0.021 mol BaCl2 </span>
<span>4)Find
the ratio of mol H2O to mol BaCl2: </span>
<span>0.044 mol
H2O : 0.021 mol BaCl2 </span>
<span>5) The
resulting ratio is 2:1 so two H2O for each BaCl2, thus, the hydrate was named: </span>
<span>Barium
chloride di-hydrate</span></span>