Chemistry Calculations Tonight !!!!!!!!!

1 Oxygen mass: 20+ grams.

2 2h2o2==2h2o+o2

x grams. So x=grams.

So the quality fraction is:

3. To prepare the solution, the key is that the solute remains unchanged. Solubility = 100 g x 3% = 3 g.

The mass of the concentrated solution is 3 grams.

1.Be.

2 2h2o2==2h2o+o2

x grams. So x=grams.

So the quality fraction is:

3. To prepare the solution, the key is that the solute remains unchanged. Solubility = 100 g x 3% = 3 g.

The mass of the concentrated solution is 3 grams.

The first question is 20+

The second question is to write the equation 2H2O2=2H2O+O2 (gas) x

Column scale 68 32=x

Solve x = calculate the mass fraction of H2O2.

The third question requires the mass of the solution to be y has: y*

Solve y=

If there are no other conditions, go and change the solution to 20g

And what does it mean.

There are three ways to determine a suspicious value.

Test. Test. 3.Grubbs test. You can use the Q test for this question.

Q-test: Arrange the data from small to large. x1q=(x2-x1) (xn-x1) x1 is an outlier.

q=(xn-x(n-1)) (xn-x1) xn is an outlier.

Compare the calculated q with the q obtained by looking up the table, and if q<=q table is true.

a= n=6 Q table = should be discarded.

Grubbs test: The data is also arranged from small to large.

t=(xaverage-x1) s x1 is the outlier and s is the standard deviation.

t=(xn-x average) s xn is the outlier and s is the standard deviation.

Comparing t to (t table) and t<=t table is true.

a= n=6 to get the table t table = do the math (do the math yourself).

To determine whether there is a significant difference between the two analysis methods, the F-test can be used.

f=s 2 large s 2 small s 2 large is the square of the larger standard deviation and s 2 small is the square of the smaller standard deviation obtained.

If the obtained data are compared with f, there is no significant difference if it is less than or equal to.

Look up the table to get f= results and do it yourself!

Hope it helps.

1.Average first.

1st bet x0= 2nd bet y0=

In finding the standard deviation s, use the g-value method to calculate g=(xi-x0) s to calculate the ratio of g and a.

CaCO3 == High temperature == Cao + CO2

x solution gives x = 8

The mass fraction of calcium carbonate in this calcium supplement tablet = 8 10 * 100% = 80% is conserved according to mass.

10+y= The mass of dilute hydrochloric acid added before the solution reaction y=100 grams.

1. Calculate the amount of the substance n according to the amount of carbon dioxide collected; It is also the amount of the substance of calcium carbonate, thus calculating the mass of calcium carbonate. 2. The mass fraction of calcium carbonate in calcium tablets is equal to the mass of calcium carbonate divided by 10 grams, 3. Calcium carbonate and hydrochloric acid are a one-to-two reaction, and the amount of calcium carbonate is known to know the hydrochloric acid, and you can find it!

Dilute sulfuric acid contains H2SO4 and the quality is contained.

The amount of H2SO4 substance is.

2naoh+h2so4=na2so4+2h2oxmol

Hydroxide talks about the amount of splitting friends of the source of sodium substances =

50 ml of mixed solution of FeCl3 and CuCl2.

The concentrations of FeCl3 and CuCl2 were 1mol l1mol l*

Therefore, the mixed solution contains FeCl3 and CuCl2 Fe3+--3NaOH each

xcu2+--2naoh

y solution x= y=

NaOH solution contains NaOH in total

The concentration of NaOH solution is:

The product is Fe(Oh)3 Cu(OH)2, so the amount of Fe3+ Cu2+ ionic species is calculated as, 3NaOH + Feci3 = Fe(OH)3 (plus precipitation arrow) + 3NaCl2NaOH + Cuci2=Cu(OH)2 (plus precipitation arrow) + 2NaCl The amount of OH in the reaction is .

So the NAOH that participates in the reaction is.

The concentration of NaOH solution is:

1. The reduced mass is 100g+ for the mass of H2

n(h2)=

v(h2)=

2. The reaction that occurs is zn+h2so4=znso4+h2n(zn)=n(h2)=

m(zn)=

The purity is 13 15 * 100% =

3. The solute after the reaction is ZnSO4

m（znso4）=

The quality score is: