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3 years ago

You find small pieces of ice instead of ice cubes in the freezer. State how this is possible.

1 answer:

4 0

Well, if u had a spilled liquid in there (we'll simply go with water) and you had the freezer at a cold temperature it would change (like,icycles on trees when it's snowing)

You might be interested in

Scientists who possess this attitude always report their observations and results truthfully.

vesna_86 [32]

I believe the correct answer from the choices listed above is the third option. Scientists who possess honesty always report their observations and results truthfully. It connotes positive and virtuous attributes such as integrity, truthfulness, straightforwardness. Hope this answers the question.

7 0

3 years ago

Excess oxygen gas (O2) reacts with 244g of Iron (Fe) to produce 332 g of Fe2O3. What is the percent yield?

Andru [333]

Answer:

95.15%

Explanation:

To calculate the percent yield, we need the following formula:

$\% yield=\dfrac{actual yield}{theoreticalyield}\times100\%$

Solving for the theoretical yied, you need to predict how much of the product will be produced if we USE up the given.

Our given is 224g of Fe and we to get the theoretical yield, we need to figure out how much product will Fe produce supposing that we use up all the reactant.

First thing we do is get the balance equation of this chemical reaction:

4Fe + 3O₂ → 2Fe₂O₃

We get the ratio between Fe and the the product, Fe₂O₃

$\dfrac{4moles of Fe}{2molesofFe_{2}O_{3}}=\dfrac{2moles of Fe}{1moleofFe_{2}O_{3}}$

This basically means that we need 2 moles of Fe to produce 1 mole of Fe₂O₃. We'll use this later.

Now we let's use our given:

We need to first convert our given to moles. To do this, we need to determine how many grams there are of the reactant for every mole. We need to first get the atomic mass of the elements involved in the substance:

Iron(1)

Fe = 55.845(1) = 55.845g/mole(1)

Then we use this to convert grams to moles

$244g\times\dfrac{1mole}{55.845g}=4.369moles$

This means that there are 4.396moles of Fe in 244g of Fe.

This we will use to see how many moles of product we can produce given the moles of reactant by using the reactant:rproduct ratio.

$4.369moles of Fe\times\dfrac{1moleofFe_{2}O_{3}}{2molesofFe}=2.185 moles of Fe_{2}O_{3}$

So given 4.693 moles of Fe we can produce 2.185 moles of Fe₂O₃

The next step is to get how many grams of product there are given our calculation. We do this again by getting how many grams of Fe₂O₃ there are in 1 mole.

Fe(2) O(3)

Fe₂O₃=55.845(2) + 15.999(3)

= 111.69 + 47.997 =159.687g/mol

We then use this to solve for how many grams of product there are in 2.185 moles.

$2.185moles\times\dfrac{159.687g}{1mole}=348.92g$

This is our theoretical yield 348.92g of Fe₂O₃.

We can finally use our percent yield equation. Our actual yield is given by the probelm, 332g of Fe₂O₃ and we solved for our theoretical yield which is 348.92g of Fe₂O₃. We plug this in our formula and solve.

$\%yield=\dfrac{actual yield}{theoreticalyield}\times100\%$

$\%yield=\dfrac{332gofFe_{2}O_{3}}{348gofFe_{2}O_{3}}\times100\%=95.15\%$

So the answer is 95.15%

3 0

3 years ago

What is homologous series . Write it's characteristics

Anni [7]

Answer:

Homologous series is defined as a systematic order of structurally similar organic compound containing same functional group in their family and two adjacent members differ in their molecular formula by -CH2 unit.

Characteristics:

1.Various members of homologous series contain same functional group.

2.Various members of homologous series can be represented by common formula.

3. All members of a homologous series have almost similar chemical properties.

4. All members have common method of preparation.

5.Two successive members of homologous series have different chain length or difference in their molecular formula by -CH2 unit.

6.The members of homologous series show different physical properties.

4 0

3 years ago

How much of a 15.0M stock solution do you need to prepare 250ml of a 2.35ml hf solution?

Svetradugi [14.3K]

Using the relationship M1V1 = M2V2 where M1 and M2 are the molar concentrations (mol/L or mmol/ml) and V1 and V2 are the volumes of the solutions, we can arrive at the following answer for the given problem:

15.0M (L of stock solution) = 2.35M (0.25L) *all volumes were converted to liters.

L of stock solution = (2.35*0.25)/15.0

Therefore, 0.0392L or 39.17 ml of stock solution is needed.

3 0

3 years ago

What mass of carbon is present in 1.4*x10^20 molecules of sucrose?

Alenkinab [10]

No of moles of Carbon, C = mass/ molar mass.
Molar mass of carbon = 12.0107. We only have to calculate the no of moles
of carbon to obtain carbon's mass. .
From Sucrose chemical formula C12H22O11 we know that there are 12
carbon atoms.
So there are 1.4x10^(20) x12 = 16.8 x 10^20 carbon atoms.
We will use avogardo's number to find out the number of carbon molecules
in the compound.
From Avogadro's no. One mole of any substance equals to 6.022140857
atoms.

So X mole contains 16.8 * 10^(20) carbon atom
(16.8x10^20 carbon atoms)/6.022 x10^23 particles/mol = 0.00279 mols
The molar mass of carbon is 12.0107g/mol so we'll multiply to get the mass:
0.00279 mols x 12 = 0.03348.

4 0

3 years ago