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2 years ago

How many silicon atoms are there in 28.09 g of Si?

Chemistry

2 answers:

irinina [24]2 years ago

8 0

Explanation:

28.09 g of silicon contains 6.02×1023 6.02 × 10 23 silicon atoms.

mixer [17]2 years ago

3 0

1 mole = 6.02.10²³ particles (atoms, moleculs, ions)

mole Si = mass : molar mass

mole Si = 28.09 : 28.09 = 1

number of atoms = 1 x 6.02.10²³ = 6.02.10²³ atoms

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How many Cl atoms are in Zn(ClO3)2?<br> O A. 2<br> O B. 1<br> O c. 3<br> O D. 6

White raven [17]

The answer cl atoms are in zn(cio3)2 is A:2 because I looked it up and it gave me 2.

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3 years ago

How many salt and water would you use to prepare 10% salt solution?

tatuchka [14]

Answer:

We can make 10 percent solution by volume or by mass. A 10% of NaCl solution by mass has ten grams of sodium chloride dissolved in 100 ml of solution. Weigh 10g of sodium chloride. Pour it into a graduated cylinder or volumetric flask containing about 80ml of water.

Explanation:

have a good day

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3 years ago

Consider the reaction of A(g) + B(g) + C(g) => D(g) for whichthe following data were obtained:

AveGali [126]

Answer:

rate= k[A]²[B]²[C]

Explanation:

When concentration of A is increased two times ,keeping other's concentration constant , rate of reaction becomes 4 times .

So rate is proportional to [A]²

When concentration of B is increased two times , keeping other's concentration constant,rate of reaction becomes 4 times.

So rate is proportional to [B]²

When concentration of C is increased two times , keeping other's concentration constant, rate of reaction becomes 2 times.

So rate is proportional to [C]

So rate= k[A]²[B]²[C]

5 0

3 years ago

Match the following aqueous solutions with the appropriate letter from the column on the right.1. 0.19 m AgNO3 2. 0.17 m CrSO4 3

vichka [17]

Answer:

0.13 m of $Mn(NO_3)_2$ → Highest boiling point

0.19 m of $AgNO_3$ → Second Highest boiling point

0.17 m of $CrSO_4$ → Third highest boiling point

0.31 m Sucrose (nonelectrolyte) → Lowest boiling point

Explanation:

Elevation in boiling is given by :

$\Delta T_b=i\times k_b\times m$

Where :

i = van't Hoff factor

$k_b$ = Molal Elevation constant of solvent

m = molaity of the solution

1) 0.19 m of $AgNO_3$

$AgNO_3\rightarrow Ag^++NO_3^{-}$

i = 2 (electrolyte)

Molality of the solution = 0.19

Elevation is boiling point of solution:

$\Delta T_b=2\times k_b\times 0.19 m$

$\Delta T_b=0.38 m\times k_b$

2) 0.17 m of $CrSO_4$

$CrSO_4\rightarrow Cr^{2+}+SO_4^{2-}$

i = 2 (electrolyte)

Molality of the solution = 0.17

Elevation is boiling point solution :

$\Delta T_b=2\times k_b\times 0.17 m$

$\Delta T_b=0.34 m\times k_b$

3) 0.13 m of $Mn(NO_3)_2$

$Mn(NO_3)_2\rightarrow Mn^{2+}+2NO_3^{-}$

i = 3 (electrolyte)

Molality of the solution = 0.13

Elevation is boiling point solution :

$\Delta T_b=3\times k_b\times 0.13 m$

$\Delta T_b=0.39 m\times k_b$

4) 0.31 m Sucrose (nonelectrolyte)

i = 1 ( non electrolyte)

Molality of the solution = 0.31 m

Elevation is boiling point solution :

$\Delta T_b=1\times k_b\times 0.31 m$

$\Delta T_b=0.31 m\times k_b$

Higher the value of elevation in temperature higher will be the boiling point of the solution .

The decreasing order of solution from highest boiling point to lowest boiling point is :

$0.39 m\times k_b>0.38 m\times k_b>0.34 m\times k_b>0.31 m\times k_b$

0.13 m of $Mn(NO_3)_2$ → Highest boiling point

0.19 m of $AgNO_3$ → Second Highest boiling point

0.17 m of $CrSO_4$ → Third highest boiling point

0.31 m Sucrose (nonelectrolyte) → Lowest boiling point

6 0

3 years ago

What is the significant digit in 23.45

klio [65]

If you mean the number of Significant Figures/Digits in 23.45, it would be 4. This is because every single non-zero digit is counted as a significant figure

7 0

3 years ago