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2 years ago

Do you think that the human being is the center of the universe?

1 answer:

3 0

I think that the sun is the center of the universe, not a human being. Everything revolves around the sun, not someone. U know when to sleep, when the time is, and when to wake up based on the sun. All the planets revolve around it. This is why I think the sun is the center of the universe, not a human being.

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A 14.3 g sample of HF is dissolved into 250 mL of solution. The concentration of the solution is *

STALIN [3.7K]

Answer:

The concentration of the solution is 2.86 M

Explanation:

Molarity is a unit of concentration based on the volume of a solution. It is defined as the number of moles of solute that are dissolved in a given volume. In other words, molarity is defined as the number of moles of solute per liter of solution.

The Molarity of a solution is determined by the following expression:

$Molarity (M)=\frac{number of moles of solute}{Volume}$

Molarity is expressed in units ( $\frac{moles}{liter}$ ).

In this case, you must then know the number of moles of HF, for which you must know the molar mass. Being:

H: 1 g/mole
F: 19 g/mole

the molar mass of HF is: HF= 1 g/mole + 19 g/mole= 20 g/mole

Then the following rule of three applies: if 20 g of HF are available in 1 mole, 14.3 g in how many moles will they be?

$moles=\frac{14.3 g*1 mole}{20 g}$

moles= 0.715

So:

number of moles of solute: 0.715 moles
Volume: 250 mL=0.250 L (being 1 L=1000 mL)

Replacing:

$Molarity=\frac{0.715 moles}{0.250 L}$

Solving:

Molarity= 2.86 $\frac{moler}{liter}$ =2.86 M

The concentration of the solution is 2.86 M

6 0

2 years ago

FeCl3(aq) + Na3PO4(aq) --> FePO4(s) + NaCl(aq) [unbalanced]

Elanso [62]

Na3Po4(aq) + FeCl3(aq) = 3 NaCl(aq) + FePo4(s)

7 0

3 years ago

Read 2 more answers

Can colloidal suspensions be separated out by filtration

balu736 [363]

Answer:

Colloidal can not be separated through filtration.

Suspension can be separated through filtration.

Explanation:

Colloidal:

Colloidal consist of the particles having size between 1 - 1000 nm i.e, 0.001- 1μm. While the pore size of filter paper is 2μm. That's why we can not separate the colloidal through the filtration. However it can be separated through the ultra filtration. In ultra filtration the pore size is reduced by soaking the filter paper in gelatin and then in formaldehyde. This is only in case of when solid colloidal is present, if colloid is liquid , there is no solid particles present and ultra filtration can not be used in this case.

Suspension:

The particle size in suspension is greater than 1000 nm. The particles in suspension can be separated through the filtration. These particles are large enough and can be seen through naked eye.

5 0

3 years ago

Read 2 more answers

If you have 30.O g of hydrogen gas burned in excess oxygen how many moles of water can you make

vladimir1956 [14]

Answer:

15 moles

Explanation:

Data given:

mass of hydrogen (H₂) = 30.0 g

amount of oxygen (O₂) = excess

moles of water = ?

Solution:

First we look to the reaction in which hydrogen react with oxygen and make (H₂O)

Reaction:

2H₂ + O₂ -----------> 2H₂O

Now look at the reaction for mole ratio

2H₂ + O₂ -----------> 2H₂O

2 mole 2 mole

So it is 2:2 mole ratio of hydrogen to water

As we Know

molar mass of H₂ = 2(1) = 2 g/mol

molar mass of H₂O = 2(1) + 16 = 18 g/mol

Now convert moles to gram

2H₂ + O₂ -----------> 2H₂O

2 mole (2 g/mol) 2 mole (18 g/mol)

4 g 36 g

So,

we come to know that 4 g of hydrogen gives 36 g of water then how many grams of water will be produce by 30 grams of hydrogen.

Apply unity formula

4 g of H₂ ≅ 36 g of H₂O

30 g of H₂ ≅ X of H₂O

Do cross multiplication

X of H₂O = 30 g x 36 g / 4 g

X of H₂O = 270 g

Now convert grams of H₂O into moles

No. of moles = mass in grams/molar mass

Put values in above formula

No. of moles = 270 g / 18 (g/mol)

No. of moles = 15 mol

so 30 gram of hydrogen produce 15 mol of water.

5 0

3 years ago

Which equation is correctly balanced?

ludmilkaskok [199]

Answer:

C) 2 H₂ + O₂ → 2 H₂O

Explanation:

4 atoms of hydrogen on reactant side

2 atoms of oxygen on reactant side

4 atoms of hydrogen on product side

2 atoms of oxygen on product side

6 0

3 years ago