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3 years ago

What is a cause of human population decrease

Chemistry

2 answers:

anzhelika [568]3 years ago

4 0

Death, sickness, loss of food and homes, many things tbh

Tresset [83]3 years ago

3 0

War diseases can you give a certain year or somthing?

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How many atoms of hydrogen are in 0.500 mol of ch3oh molecules?

cestrela7 [59]

In 1 mol of CH3OH, you have 4 H-atoms (because 3 H-atoms are attached to the C-atom, and one H-atom in the OH group). That means in 0.500 mol of CH3OH, you have 2 H-atoms since it is halved. And then we have Avogadro's constant: 6.02 * 1023.

The question asks for how many hydrogen atoms there are in 0.500 mol CH3OH. Using the numbers that we have (Avogadro's constant and no. of H-atoms), the answer of the question will be something like:

H-atoms in CH3OH = 2 * 6.02 * 1023 = ~1.2 * 1024

8 0

3 years ago

A sample of propane(c3h8)has 3.84x10^24 H atoms.

deff fn [24]

Answer:

A) 14. 25 × 10²³ Carbon atoms

B) 34.72 grams

Explanation:

1 molecule of Propane has 3 atoms of Carbon and 8 atoms of Hydrogen.

The sample has 3.84 × 10²⁴ H atoms.

If 8 atoms of Hydrogrn are present in 1 molecule of propane.

3.84 × 10²⁴ H atoms are present in

$\mathfrak{ \frac{3.8 }{8} \times 10 ^{24}}$

= 4.75 × 10²³ molecules of Propane.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

No. of Carbon atoms in 1 molecule of propane = 3

=> C atoms in 4.75× 10²³ molecules of Propane = 3 × 4.75 × 10²³

= 14.25 × 10²³ 

________________________________________

Gram Molecular Mass of Propane(C3H8)

= 3 × 12 + 8 × 1

= 36 + 8

= 44 g

1 mole of propane weighs 44g and has 6.02× 10²³ molecules of Propane.

=> 6.02 × 10²³ molecules of Propane weigh = 44 g

=> 4. 75 × 10²³ molecules of Propane weigh =

$\mathsf{ \frac{44 }{6.02 \times {10}^{23} } \times 4.75 \times {10}^{23} }$

$\mathsf{ = \frac{44 }{6.02 \times \cancel{{10}^{23} }} \times 4.75 \times \cancel{ {10}^{23}} }$

$\mathsf{ = \frac{44 }{6.02 } \times 4.75 }$

= 34.72 g

8 0

2 years ago

H is a chemical _____ and H2 is a chemical ______

jeyben [28]

I don’t know if I am right but I think it is symbol for the first one and the second one is formula.

4 0

3 years ago

Read 2 more answers

How many grams of pure naoh must be used to prepare 10.0 l of a solution that has a ph of 13? __________g?

padilas [110]

40 g NaOH. You must use 40 g NaOH to prepare 10.0 L of a solution that has a pH of 13.

Step 1. Calculate the pOH of the solution

pOH = 14.00 – pH = 14.00 -13 = 1

Step 2. Calculate the concentration of NaOH

[NaOH] = [OH^(-)] = 10^(-pOH) mol/L = 10^(-1) mol/L = 0.1 mol/L

Step 3. Calculate the moles of NaOH

Moles of NaOH = 10.0 L solution × (0.1 mol NaOH/1 L solution) = 1 mol NaOH

Step 4. Calculate the mass of NaOH

Mass of NaOH = 1 mol NaOH × (40.00 g NaOH/1 mol NaOH) = 40 g NaOH

8 0

3 years ago

Write the balanced net reaction for the following half cells: Sn2+ / Sn Cr2+ / Cr

GuDViN [60]

The balanced net reactiion for the following half cells will be

Sn + Cr²⁺ ---> Sn²⁺ + Cr

<h3>What are Half cells ?</h3>

A half cell is one of the two electrodes of an electrochemical cell.

An electrochemical cell comprises two half cells, where every half cell contains an electrode and an electrolyte.

A salt bridge or direct contact is needed to connect two half cells.

The balanced net reactiion for the given half cells will be

Sn + Cr²⁺ ---> Sn²⁺ + Cr

Learn more about Half cell here ;

brainly.com/question/1313684

#SPJ1

4 0

2 years ago