the crucible is not fired, as the procedure suggests, but had retained some impurities from previous use(or it could be oily smudges from fingers). the mass of the "dirty" crucible is recorded. however the impurities are burned off in the experiment. how does this affect the reported mass of the final product? explain

1. 👍 0
2. 👎 0
3. 👁 1,104
1. What is your SCHOOL SUBJECT?

1. 👍 0
2. 👎 0
2. This must be a chemistry question and you gave VERY little evidence of what you are working on. However, in general, let's make up some numbers.
15.00 g = clean xble
17.00 g = xble + our ppt
----------
2.00 g = mass ppt.

BUT suppose the xble is dirty, as the problem suggests, so it actually weighs 16.00 g = mass clean xble + dirt
When we add the ppt to the dirty xble, we have
15.00 clean xble
1.00 g dirt
2.00 g ppt
-----
Total 18.00 g

Now we fire it, the dirt burns off and it will weigh
15.00 g for clean xble
+2.00 for ppt
Total is 17.00
and when we subtract 17.00-16.00 = 1.00 g ppt which of course is wrong. We actually had 2.00 g ppt; therefore, the mass of the reported material is too low.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Composite Materials

Can someone please help with this problem? A burnout test was performed to determine the volume fractions of constituents in a glass/epoxy composite. The following observations were made: Weight of empty crucible = 47.6504 g

2. ### General chemistry

1) How high above the inner blue cone of the burner flame should the crucible be when the Mg is heated? 2) What should you do if you see white smoke rising from the crucible in the early stages of heating the Mg? 3) How will you

3. ### English

Can you check this please Our job, it emerges from fragments throughout the day, is to keep ladies’ wear “shoppable.” Sure, we help customers (who are increasingly called “guests” here as well), if they want any help. At

4. ### Chemistry

I'm going over some post-laboratory questions for Conductivity of Solutions. One of the questions is... From your measurements, what can you say about a) the presence of ionic impurities in tap water? b) the presence of molecular

1. ### Physics

A non-rotating spherical planet with no atmosphere has a mass M and radius R. A particle is fired off from the surface with a speed equal to 3/4 the escape speed. Calculate the farthest distance it reaches (measured from the

2. ### chemistry

In a magnesium oxide experiment Describe the effect of the following factors, whether decrease, increase, or has no effect on the reported value of Mg to O mole ratio: a) if carbon is deposited on the crucible's surface(due to

3. ### Analytical Chemistry

Match the following terms about analytical precipitations to their definitions: A.) Coprecipitation B.) Adsorption C.) Absorption D.) Gathering E.) Masking F.) Digestion G.) Peptization 1.) Inclusion or occlusion of impurities

4. ### Chemistry

Weight of empty crucible and cover = 23.104 g Weight of crucible, cover, MgO and Mg3N2 = 24.199 g Weight of crucible, cover, MgOand addition of H2O and heat = 24.290 Calculate the number of moles of Mg3N2.

1. ### Chemistry

A hydrated MgSO4 salt, weighing 3.211g, is heated in a crucible until reaching a constant weight. The weight of the anhydrous MgSO4 is 1.570 grams. 1. Calculate the moles of H20 removed and the moles of anhydrous MgSO4 remaining

2. ### Chemistry

if some volatile impurities in the crucible are not burned off in step 1 but are removed in step 4 is the reported percent mass of water in the hydrated salt too high or too low?

3. ### General Chemistry

The formula of a compound of lead (Pb) and sulfur (S) was determined using the method in this module. A sample of Pb was weighed into a crucible and covered with finely powdered S. The crucible was covered and heated to allow the

4. ### Pre-Calculus

10. Suppose the cost C of removing p% of the impurities from the waste water in a manufacturing process is given by a) Where does the graph of this function have a vertical asymptote? b) What does this tell us about removing the