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3 years ago

How many moles are in 20g of potassium (K)?

Chemistry

1 answer:

otez555 [7]3 years ago

7 0

Explanation:

Hi for this one u just need to remember and use the equation.

$moles = \frac{mass}{mr}$

then u find mr of potassium which is 39.1.

then u do

$\frac{20}{39.1}$

you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .

hope this helps :)

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A flask contains 6g hydrogen gas and 64 g oxygen at rtp the partial pressure of hydrogen gas in the flask of the total pressure

Alex

Answer:

B.3/5p

Explanation:

For this question, we have to remember "Dalton's Law of Partial Pressures". This law says that the pressure of the mixture would be equal to the sum of the partial pressure of each gas.

Additionally, we have a proportional relationship between moles and pressure. In other words, more moles indicate more pressure and vice-versa.

$P_i=P_t_o_t_a_l*X_i$

Where:

$P_i$ =Partial pressure

$P_t_o_t_a_l$ =Total pressure

$X_i$ =mole fraction

With this in mind, we can work with the moles of each compound if we want to analyze the pressure. With the molar mass of each compound we can calculate the moles:

moles of hydrogen gas

The molar mass of hydrogen gas ( $H_2$ ) is 2 g/mol, so:

$6g~H_2\frac{1~mol~H_2}{2~g~H_2}=~3~mol~H_2$

moles of oxygen gas

The molar mass of oxygen gas ( $O_2$ ) is 32 g/mol, so:

$64g~H_2\frac{1~mol~H_2}{32~g~H_2}=~2~mol~O_2$

Now, total moles are:

Total moles = 2 + 3 = 5

With this value, we can write the partial pressure expression for each gas:

$P_H_2=\frac{3}{5}*P_t_o_t_a_l$

$P_O_2=\frac{2}{5}*P_t_o_t_a_l$

So, the answer would be 3/5P.

I hope it helps!

5 0

3 years ago

How will you ensure your server is protected from data hacks?

mario62 [17]

Close all network ports, filter those you can't block

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3 years ago

Read 2 more answers

The reaction is found to be first order in IO3−, first order in SO32−, and first order in H+. If [IO3−]=x, [SO32−]=y, and [H+]=z

ollegr [7]

Answer:

rate = kxyz

Explanation:

It is worth knowing that the rate low can only be determined by experimentation only not by just balancing equations. So here we are told that all the reactants x , y and z are all first order. This is important because we use this as exponents. That is why the exponents of all the reactants will be 1.

rate = kxyz

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3 years ago

Which half-reaction correctly represents reduction? *

nasty-shy [4]

Answer:

Explanation:

Reduction can be seen through addition (gaining) of electrons, addition of Hydrogen or removal of Oxygen

Mn7+ is reduced to Mn4+ by the addition of 3 electrons.

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3 years ago

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8090 [49]

Answer:

the answer is C

Explanation:

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3 years ago