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3 years ago

Hello :) how to do this?

Chemistry

2 answers:

Nina [5.8K]3 years ago

7 0

Answer:

i dk

Explanation:

juin [17]3 years ago

4 0

Answer:

28g/ dm³

0.5 M

Explanation:

1dm³= 1000cm³

Let's convert the volume to cm³.

Volume of solution

= 200cm³

= (200÷1000) dm³

= 0.2 dm³

Concentration in g/dm³ means the amount of solute, KOH, in 1 dm³ of solution.

In 0.2 dm³, there is 5.6g of KOH.

Thus in 1 dm³, amount of KOH

= 5.6 ÷0.2

= 28g

Concentration in g/dm³ is 28g/dm³.

Molarity is a concentration unit. It is the number of moles of solvent in 1 L or 1dm³ of solution. Since we have already found the mass of KOH in 1dm³ of solution, we will use dm³.

1dm³ ----- 28g of KOH

moles= mass ÷mr

Molecular mass of KOH

= 39 +16 +1

= 56

1dm³ ----- 28 ÷56= 0.5 moles of KOH

Thus, concentration in molarity is 0.5M.

(Unit for molarity is M)

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How many moles are in 2.31*10^21 atoms of lead

Anon25 [30]

Hey there!:

Molar mass Lead ( Pb ) = 207.2 g/mol

Therefore:

1 mole Pb --------------------- 6.02*10²³ atoms
? moles Pb -------------------- 2.31*10²¹ atoms

moles Pb = ( 2.31*10²¹ ) * 1 / ( 6.02*10²³ ) =

moles Pb = ( 2.31*10²¹ ) / ( 6.02*10²³ ) =

=> 0.00383 moles of Pb

Hope this helps !

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3 years ago

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nikklg [1K]

Explanation :

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(b) $S_8(s)+8O_2(g)\rightarrow 8SO_2(g)$

This reaction is a redox reaction or oxidation-reduction reaction in which sulfur get oxidized and oxygen get reduced.

(c) $2Al(s)+3Cl_2(g)\rightarrow 2AlCl_3(s)$

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(d) $2AlN\rightarrow 2Al(s)+N_2(g)$

This reaction is a decomposition reaction in which a large molecule or reactant decomposes to give two or more molecule or products.

(e) $BaCl_2(aq)+Na_2SO_4(aq)\rightarrow BaSO_4(s)+2NaCl(aq)$

This reaction is a double displacement reaction in which the cation of two reactants molecule exchange their places to give two different products.

(f) $2Cs(s)+Br_2(l)\rightarrow 2CsBr(s)$

This reaction is a combination reaction in which the two reactants combine to form a large molecule or product.

(g) $KOH(aq)+HCl(aq)\rightarrow H_2O(l)+KCl(aq)$

This reaction is a double displacement reaction in which the cation of two reactants molecule exchange their places to give two different products.

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3 years ago

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Oksana_A [137]

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3 0

3 years ago

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OverLord2011 [107]

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3 years ago

Identify the compounds that are soluble in both water and hexane.

dlinn [17]

Answer:

The compound which are boh soluble in water and hexane is

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3 years ago