All categories

4 years ago

In a 100 g sample of iron(III) oxide, how many grams of iron are present?

1 answer:

8 0

The formula of Iron(III) oxide is Fe2O3
In order to calculate the mass of iron in a given sample of iron(III) oxide, we must first know the mass percentage of iron in iron(III) oxide. This is calculated by:
[mass of iron in one mole of iron(III) oxide/ mass of one mole of iron(III) oxide] * 100
= [(moles of iron * Mr of iron) / (moles of Iron * Mr of Iron + moles of Oxygen * Mr of Oxygen)] * 100
= [(2 * 56) / (2 * 56 + 3 * 16)] * 100
= (112 / 160) * 100
= 70%
Thus, in a 100g sample, the weight of iron will be:
100 * 70%
= 70 grams

You might be interested in

Identify the independent /manipulated variable

fiasKO [112]

Answer:

independent- test variable

manipulated - outcome variable; if needed, there could be changes.

Explanation:

knowledge

7 0

3 years ago

When comparing the two elements K and Ge , the more metallic element is__________ based on periodic trends alone.

Inessa [10]

Answer:

Option D and Option B

When comparing the two elements K and Ge , the more metallic element is_____K_____ based on periodic trends alone.

When comparing the two elements Sb and Pb , the more metallic element is_____Pb______ based on periodic

Explanation:

The metallic characteristic increases when we move down a column in a periodic table or when we move left in the row.

Potassium and Germanium are located on the same row, but germanium lies on the right side of potassium. Thus, potassium (K) is more metallic than Germanium (Ge)

While Lead (Pb) lies to left of Sb in the adjacent column and is also lies below Sb. Hence Pb is more metallic than Sb

7 0

3 years ago

Analysis of the water content of a lake found in the desert showed that it contained 17.5 percent chloride ion, and has a densit

tankabanditka [31]

Answer:

The molarity is 6.0 M.

Explanation:

The concentration of a solution is the amount of solute present in a given amount of solvent, or a given amount of solution.

In this problem, we are asked to convert percent by mass to molarity, which are two different concentration units.

The percent by mass is the ratio of the mass of a solute to the mass of the solution, multiplied by 100 percent. On the other hand, molarity (M) is defined as the number of moles of solute per liter of solution.

If we have 17.15 percent chloride ion, that means that we have 17.15 grams of chloride ion in 100 grams of solution. The density provided is the density of the solution, so we calculate how many mL correspond to 100 grams of solution:

1.23 g ----------- 1 mL

100 g ------------ x= 81.3 mL

Therefore, 17.5 grams of chloride ion are contained in 81.3 mL. Now we need to convert these grams into moles.

The atomic mass of chlorine is 35.5 g/mol:

35.5 g --------------- 1 mol

17.5 g --------------- x= 0. 49 mol

This 0.49 moles are contained in 81.13 mL, the definition of molarity says that this moles are contained in a liter (or what is the same, 1000 mL):

81.3 mL --------------- 0.49 mol

1000 mL ------------- x= 6.0 M

The molarity of the chloride ion will be 6.0 M.

5 0

3 years ago

Observation and assessment are most effective when

Artist 52 [7]

I think the answer is A. Hope that helped :)

6 0

3 years ago

If the equilibrium constant of the reaction is 0.85, then which statement is true if the mass of A is 10.5 grams; the density of

snow_tiger [21]

Answer:

E. Q < K and reaction shifts right

Explanation:

Step 1: Write the balanced equation

A(s) + 3 B(l) ⇄ 2(aq) + D(aq)

Step 2: Calculate the reaction quotient (Q)

The reaction quotient, as the equilibrium constant (K), only includes aqueous and gaseous species.

Q = [C]² × [D]

Q = 0.64² × 0.38

Q = 0.15

Step 3: Compare Q with K and determine in which direction will shift the reaction

Since Q < K, the reaction will shift to the right to attain the equilibrium.

8 0

3 years ago