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3 years ago

How many moles of silicon (Si) are in 1.50 x 1023 atoms Si?

Chemistry

1 answer:

erik [133]3 years ago

8 0

Answer:

1534.5

Explanation:

you just multiply i think

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What is the mass of 2.47 moles of fluorine (<br> f. atoms? 0.130 g 7.69 g 46.9 g my answer 282 g

mixer [17]

The mass of 2.47 moles of fluorine atom is 46.9 g

calculation

mass of Fluorine= moles x molar mass

moles = 2.47 moles

molar mass of fluorine = 18.998 g/mol

mass is therefore= 2.47 moles x 18.008 g/mol = 46.9 g

3 0

4 years ago

The air bags in cars are inflated when a collision triggers the explosive, highly exothermic decomposition of sodium azide (NaN3

Oksanka [162]

Answer : The mass of $NaN_3$ required is, 166.4 grams.

Explanation :

First we have to calculate the moles of nitrogen gas.

Using ideal gas equation:

$PV=nRT$

where,

P = Pressure of $N_2$ gas = 1.00 atm

V = Volume of $N_2$ gas = 113 L

n = number of moles $N_2$ = ?

R = Gas constant = $0.0821L.atm/mol.K$

T = Temperature of $N_2$ gas = $85^oC=273+85=358K$

Putting values in above equation, we get:

$1.00atm\times 113L=n\times (0.0821L.atm/mol.K)\times 358K$

$n=3.84mol$

Now we have to calculate the moles of sodium azide.

The balanced chemical reaction is,

$2NaN_3(s)\rightarrow 2Na(s)+3N_2(g)$

From the balanced reaction we conclude that

As, 3 mole of $N_2$ produced from 2 mole of $NaN_3$

So, 3.84 moles of $N_2$ produced from $\frac{2}{3}\times 3.84=2.56$ moles of $NaN_3$

Now we have to calculate the mass of $NaN_3$

$\text{ Mass of }NaN_3=\text{ Moles of }NaN_3\times \text{ Molar mass of }NaN_3$

Molar mass of $NaN_3$ = 65 g/mole

$\text{ Mass of }NaN_3=(2.56moles)\times (65g/mole)=166.4g$

Therefore, the mass of $NaN_3$ required is, 166.4 grams.

3 0

3 years ago

Table salt contains 39.33 g of sodium per 100 g of salt. The U.S. Food and Drug Administration (FDA) recommends that adults cons

IrinaVladis [17]

<span>First set up the equation 39.33g/100g = x/1.28g and that'll give you how much sodium is in each 100g of the mix.

39.33g *1.28g= 100g * x
x = 0.503424g
x = Amount of sodium per 100g of the mix

Now 2.4g / 0.503424 = 4.7674
Multiply by 100 and you get 476.7353g</span>

4 0

3 years ago

Read 2 more answers

Which of the following is an example of a physical change?

dangina [55]

D it is only physical and not chemical

5 0

3 years ago

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an unknown molecule is found to consist of 24.2% carbon by mass, 4.0% hydrogen by mass and the remaining mass is due to chlorine

Paha777 [63]

Answer:

C3 H6 Cl 3

Explanation:

C -24.2%

H - 4.0%

Cl - (100-24.2 - 4.0)=73.8 %

We can take 100g of the substance, then we have

C -24.2 g

H - 4.0 g

Cl - 73.8 g

Find the moles of these elements

C -24.2 g/12.0 g/mol =2.0 mol

H - 4.0 g/1.0 g/mol = 4. 0 mol

Cl - 73.8 g/ 35.5 g/mol = 2.1 mol

Ratio of these elements gives simplest formula of the substance

C : H : Cl = 2 : 4 : 2 = 1 : 2 : 1

CH2Cl

Molar mass (CH2Cl) = 1*12.0 +2*1.0 + 1*35.5 = 49.5 g/mol

Real molar mass = 150 g/mol

real molar mass/ Molar mass (CH2Cl) = 150 /49.5=3

So, Real formula should be C3 H6 Cl 3.

4 0

4 years ago

Read 2 more answers