What did theodor schwann do??? for the cell theory (what is the theory)

A plastic bin is found to hold 3.1x10^24 molecules of water.

motikmotik

Answer:

$\boxed {\boxed {\sf 5.1 \ mol \ H_2O}}$

Explanation:

To convert from representative particles to moles, Avogadro's Number: 6.02*10²³, which tells us the number of particles (atoms, molecules, etc.) in 1 mole of a substance.

We can use it in a ratio.

$\frac {6.02*10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O}$

Multiply by the given number of molecules.

$3.1*10^{24} \ molecules \ H_2O*\frac {6.02*10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O}$

Flip the ratio so the molecules of water cancel out.

$3.1*10^{24} \ molecules \ H_2O*\frac {1 \ mol \ H_2O}{6.02*10^{23} \ molecules \ H_2O}$

$3.1*10^{24} *\frac {1 \ mol \ H_2O}{6.02*10^{23} }$

$\frac {3.1*10^{24} \ mol \ H_2O}{6.02*10^{23} }$

Divide.

$5.14950166113 \ mol \ H_2O$

The original number of molecules has 2 significant figures: 3 and 1, so our answer must have the same. For the number we calculated, that is the tenth place. The 4 in the hundredth place tells us to leave the 1.

$5.1 \ mol \ H_2O$

There are about 5.1 moles of water in 3.1*10²⁴ molecules of water.

5 0

3 years ago

Atomic mass of nitrogen

erma4kov [3.2K]

Hello!! Your atomic mass will be found at the bottom of each element. The atomic mass of Nitrogen is 14.007. Have a great day!!

8 0

3 years ago

Need some help with this problem please!

Tom [10]

Answer:

18 liters

Explanation:

Step 1: Figure out what the formula and what you are dealing with.

- 25 degrees celcius is constant, so it is irrelevant for the mathmatical part.

- P1 = 1 atm

- P2 = 20 atm

- V1 = 360 liters

- V2 = trying to find

Note: remember the original equation is V1/P1 = V2/P2

- Step 2: Rearrange the equation to fit this problem, you should get...

V2 = V1 x P1 / P2

- Step 3: Fill our own numbers in. You should get...

360 L x 1 atm / 20 atm = 18 Liters (do the math)

- Answer = 18 Liters

- Remember to just follow the formula and fill it in with your own numbers.

If you need any more help comment below. I am happy to help anytime.

7 0

3 years ago

Element Q has an atomic number 68. Consider the isotope Q-136 how many protons are in a neutral atom of this isotope?

mote1985 [20]

Answer: 68

Explanation:

Isotopes of an element have same number of protons but different number of neutrons. Which means isotopes of an element have same atomic number but different mass number.

Atomic number is equal to the number of protons or the number of electrons for a neutral atom and is specific to a particular element.

Mass number is the sum of number of protons and the number of neutrons.

Given : atomic number of element Q = 68 = number of protons

Mass number of isotope Q-136 = 136

But as isotopes have same atomic number, the number of protons will be same and hence there are 68 protons are in a neutral atom of this isotope.

7 0

3 years ago

Answer these please ASAP need help no idea how to do these

STALIN [3.7K]

Answer:

Explanation:

Cu:

Number of moles = Mass / molar masa

2 mol = mass / 64 g/mol

Mass = 128 g

Mg:

Number of moles = Mass / molar masa

0.5 mol = mass / 24 g/mol

Mass = g

Cl₂:

Number of moles = Mass / molar masa

Number of moles = 35.5 g / 24 g/mol

Number of moles = 852 mol

H₂:

Number of moles = Mass / molar mass

8 mol = Mass / 2 g/mol

Mass = 16 g

P₄:

Number of moles = Mass / molar masa

2 mol = mass / 124 g/mol

Mass = 248 g

O₃:

Number of moles = Mass / molar masa

Number of moles = 1.6 g /48 g/mol

Number of moles = 0.033 mol

H₂O

Number of moles = Mass / molar masa

Number of moles = 54 g / 18 g/mol

Number of moles = 3 mol

CO₂

Number of moles = Mass / molar masa

2 mol = mass / 124 g/mol

Mass = 248 g

NH₃

Number of moles = Mass / molar masa

Number of moles = 8.5 g / 17 g/mol

Number of moles = 0.5 mol

CaCO₃

Number of moles = Mass / molar masa

Number of moles = 100 g / 100 g/mol

Number of moles = 1 mol

a)

Given data:

Mass of iron(III)oxide needed = ?

Mass of iron produced = 100 g

Solution:

Chemical equation:

F₂O₃ + 3CO → 2Fe + 3CO₂

Number of moles of iron:

Number of moles = mass/ molar mass

Number of moles = 100 g/ 56 g/mol

Number of moles = 1.78 mol

Now we compare the moles of iron with iron oxide.

Fe : F₂O₃

2 : 1

1.78 : 1/2×1.78 = 0.89 mol

Mass of F₂O₃:

Mass = number of moles × molar mass

Mass = 0.89 mol × 159.69 g/mol

Mass = 142.124 g

100 g of iron is 1.78 moles of Fe, so 0.89 moles of F₂O₃ are needed, or 142.124 g of iron(III) oxide.

b)

Given data:

Number of moles of Al = 0.05 mol

Mass of iodine = 26 g

Limiting reactant = ?

Solution:

Chemical equation:

2Al + 3I₂ → 2AlI₃

Number of moles of iodine = 26 g/ 254 g/mol

Number of moles of iodine = 0.1 mol

Now we will compare the moles of Al and I₂ with AlI₃.

Al : AlI₃

2 : 2

0.05 : 0.05

I₂ : AlI₃

3 : 2

0.1 : 2/3×0.1 = 0.067

Number of moles of AlI₃ produced by Al are less so it will limiting reactant.

Mass of AlI₃:

Mass = number of moles × molar mass

Mass = 0.05 mol × 408 g/mol

Mass = 20.4 g

26 g of iodine is 0.1 moles. From the equation, this will react with 2 moles of Al. So the limiting reactant is Al.

c)

Given data:

Mass of lead = 6.21 g

Mass of lead oxide = 6.85 g

Equation of reaction = ?

Solution:

Chemical equation:

2Pb + O₂ → 2PbO

Number of moles of lead = mass / molar mass

Number of moles = 6.21 g/ 207 g/mol

Number of moles = 0.03 mol

Number of moles of lead oxide = mass / molar mass

Number of moles = 6.85 g/ 223 g/mol

Number of moles = 0.031 mol

Now we will compare the moles of oxygen with lead and lead oxide.

Pb : O₂

2 : 1

0.03 : 1/2×0.03 = 0.015 mol

Mass of oxygen:

Mass = number of moles × molar mass

Mass = 0.015 mol × 32 g/mol

Mass = 0.48 g

The mass of oxygen that took part in equation was 0.48 g. which is 0.015 moles of oxygen. The number of moles of Pb in 6.21 g of lead is 0.03 moles. So the balance equation is

2Pb + O₂ → 2PbO

6 0

3 years ago