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3 years ago

What element has an atomic mass 4?

Chemistry

2 answers:

Daniel [21]3 years ago

4 0

Answer:

Helium has atomic mass 4.002602.

So the answer to yr question is helium.

ollegr [7]3 years ago

4 0

The answer is helium

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Determine how many liters 8.65 g of carbon dioxide gas would occupy at the following conditions.

VashaNatasha [74]

1) 6.17 liters

2)2.66 liters

3 0

3 years ago

A force of 25 newtons is exerted over an area of 50 square meters. Calculate

snow_lady [41]

Answer:

the pressure exerted in pascals is 0.5 Pa

Explanation:

The computation of the pressure exerted in pascals is shown below:

As we know that

Pressure = force ÷ area

= 25 ÷ 50

= 0.5 Pa

Hence, the pressure exerted in pascals is 0.5 Pa

We simply applied the above formula so that the correct pressure could come

4 0

2 years ago

When 125 grams of FeO react with 25.0 grams of Al, how many grams of Fe can be produced? FeO + Al → Fe + Al2O3 25.9 g Fe 38.7 g

Serga [27]

<u>Answer:</u> The mass of iron produced will be 77.6 grams

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

<u>For FeO:</u>

Given mass of FeO = 125 g

Molar mass of FeO = 71.8 g/mol

Putting values in equation 1, we get:

$\text{Moles of FeO}=\frac{125g}{71.8g/mol}=1.74mol$

<u>For aluminium:</u>

Given mass of aluminium = 25.0 g

Molar mass of aluminium = 27 g/mol

Putting values in equation 1, we get:

$\text{Moles of aluminium}=\frac{25.0g}{27g/mol}=0.93mol$

The given chemical reaction follows:

$3FeO+2Al\rightarrow 3Fe+Al_2O_3$

By Stoichiometry of the reaction:

2 moles of aluminium metal reacts with 3 mole of FeO

So, 0.93 moles of aluminium metal will react with = $\frac{3}{2}\times 0.93=1.395mol$ of FeO

As, given amount of FeO is more than the required amount. So, it is considered as an excess reagent.

Thus, aluminium metal is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

2 moles of aluminium metal produces 3 mole of iron metal

So, 0.93 moles of aluminium metal will produce = $\frac{3}{2}\times 0.93=1.395moles$ of iron metal

Now, calculating the mass of iron metal from equation 1, we get:

Molar mass of iron = 55.85 g/mol

Moles of iron = 1.395 moles

Putting values in equation 1, we get:

$1.395mol=\frac{\text{Mass of iron}}{55.85g/mol}\\\\\text{Mass of iron}=(1.395mol\times 55.85g/mol)=77.6g$

Hence, the mass of iron produced will be 77.6 grams

4 0

3 years ago

The addition of 250.0 J to 30.0 g of copper initially at 22.0°C will change its temperature to what final value? (Specific heat

WINSTONCH [101]

Answer:

Final temperature = $43.53^{\circ} C$

Explanation:

Given that,

Heat added, Q = 250 J

Mass, m = 30 g

Initial temperature, T₁ = 22°C

The Specific heat of Cu= 0.387 J/g °C

We know that, heat added due to the change in temperature is given by :

$Q=mc\Delta T\\\\Q=mc(T_2-T_1)\\\\\dfrac{Q}{mc}=(T_2-T_1)\\\\T_2=\dfrac{Q}{mc}+T_1$

Put all the values,

$T_2=\dfrac{250}{30\times 0.387}+22\\\\=43.53^{\circ} C$

So, the final temperature is equal to $43.53^{\circ} C$ .

8 0

3 years ago

Table salt is also known as sodium chloride, because it is

Mnenie [13.5K]

Sodom chloride is an ionic compound.

<h3>What is sodium chloride?</h3>

Sodium chloride is a compound that is formed by the combination of sodium and chlorine atoms. The compound is ionic as the ions of the atoms combine. Sodium looses one electron that can now be gained by chlorine.

Since the compound is ionic, it has a high melting and boiling point. This implies that the compound could melt as high as 801 degrees centigrade. The boiling point of the compound is much higher.

We can represent the compound using the ball and stick or the space filling model. The ball and stick model of sodium chloride has been shown in the image attached to this answer.

Learn more about ball and stick model:brainly.com/question/17217225

#SPJ1

6 0

1 year ago