1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mina [271]
2 years ago
6

Calculate the number of hydrogen atoms present in 40g of urea, (NH2)2CO

Chemistry
1 answer:
tekilochka [14]2 years ago
7 0

Answer: There are 16.14 \times 10^{23} atoms of hydrogen are present in 40g of urea, (NH_{2})_{2}CO.

Explanation:

Given: Mass of urea = 40 g

Number of moles is the mass of substance divided by its molar mass.

First, moles of urea (molar mass = 60 g/mol) are calculated as follows.

Moles = \frac{mass}{molar mass}\\= \frac{40 g}{60 g/mol}\\= 0.67 mol

According to the mole concept, 1 mole of every substance contains 6.022 \times 10^{23} atoms.

So, the number of atoms present in 0.67 moles are as follows.

0.67 mol \times 6.022 \times 10^{23} atoms/mol\\= 4.035 \times 10^{23} atoms

In a molecule of urea there are 4 hydrogen atoms. Hence, number of hydrogen atoms present in 40 g of urea is as follows.

4 \times 4.035 \times 10^{23} atoms\\= 16.14 \times 10^{23} atoms

Thus, we can conclude that there are 16.14 \times 10^{23} atoms of hydrogen are present in 40g of urea, (NH_{2})_{2}CO.

You might be interested in
A salt solution with a volume of 250 mL that contains 0.70 mol NaCl.
uysha [10]
 <span>0.70 mol/0.250 L = 2.8 M</span>
5 0
3 years ago
How many moles of Mg are present in 62.23 grams of Mg? (Show your calculations for full credit.)
mylen [45]
62.23 = 1512.5001499999998 moles
5 0
2 years ago
What happens when a solid is dissolved in a liquid
slava [35]

the solid particles take up the intermolecular spaces in the liquid.

8 0
3 years ago
Write the balanced chemical equation for the following reaction. Phases are optional. Solid calcium chlorate decomposes to form
Tanya [424]

Answer:

  • Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)

Explanation:

1)<u> Word equation (given)</u>

  • <em>calcium chlorate (solid) → solid calcium chloride (solid)  + oxygen (gas)</em>

2) <u>Chemical formulae of the reactant and products</u>:

  • <em><u>Calcium chlorate</u></em><em>: </em>

The most common oxidation states of chlorine are -1, +1, +3, +5, +7.

The suffix ate in chlorate means that chlorine atom is with the third lowest oxidation state (counting only the positive states). So, this is +5.

The oxidation state of calcium is +2.

Hence, the chemical formula of calcium chlorate is Ca(ClO₃)₂

  • <u><em>Calcium chloride</em></u>

The suffix ide in chloride means that chlorine is with oxidation state -1. Again the oxidation state of calcium is +2.

Hence, the chemical formula of calcium chloride is CaCl₂

  • <u><em>Oxygen</em></u>

Oxygen gas is a diatomic molecule, so its chemical formula is O₂.

  • <u><em>Phases</em></u>

The symbols s and g (in parenthesis) indicate the solid and gas phases respectively.

3) <u>Chemical equation</u>:

  • Ca(ClO₃)₂ (s) → CaCl₂ (s) + O₂ (g)

That equation is not balanced becasue the number of O atoms in the reactant side and in the product side are different.

4)<u> Balanced chemical equation:</u>

Add a 3 as coefficient in front of O₂(g), in the product side to balance:

  • Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)

Verify that all the atoms are balanced:

Atom    Reactant side      Product side

Ca             1                           1

Cl              2                          2

O              3×2 = 6                2×3 = 6

Conclusion: the equation is balanced and the final answer is:

  • Ca(ClO₃)₂ (s) → CaCl₂ (s) + 3O₂ (g)
5 0
3 years ago
Which is true about the total mechanical energy in a closed system?
ryzh [129]
It’s between C and B
3 0
3 years ago
Read 2 more answers
Other questions:
  • [Send a message] as you move across a row from left to right in the period table, atomic numbers of the elements
    14·1 answer
  • When 2.499 g of AX (s) dissolves in 135.3 g of water in a coffee-cup calorimeter the temperature rises from 23.6 °C to 35.2 °C.
    14·1 answer
  • One of the main characteristics Of a solid is that they__.
    14·2 answers
  • What is the pH of a solution of KOH with a hydroxide concentration of [OH⁻] = 1.10 x 10⁻⁴
    6·1 answer
  • Is a hydrogel a smart polymer/stimuli-responsive polmer?​
    6·2 answers
  • WHAT HAPPENS WHEN ELECTRIC CURRENT PASSES THROUGH ACIDIFIED WATER.
    14·2 answers
  • Explain one way the water cycle affects climate. Use complete sentences.
    12·1 answer
  • Definition of property change.<br>chemistry ​
    9·1 answer
  • Copper metal (Cu) reacts with silver nitrate (AgNO3) in aqueous solution to form Ag and Cu(NO3)2. The balanced chemical equation
    6·1 answer
  • Phase change involves changing states of matter (solid-liquid-gas). How do these three states of matter differ from each other?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!