Hydrogen peroxide slowly decomposes in light:

A gold coin contains 3.47 × 10^23<br> gold atoms.<br> What is the mass of the coin in grams?

VashaNatasha [74]

Answer:

Mass = 114.26 g

Explanation:

Given data:

Number of gold atoms = 3.47×10²³ atoms

Mass in gram = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

3.47×10²³ atoms × 1 mol /6.022 × 10²³ atoms

0.58 mol

Mass of gold:

Mass = number of moles × molar mass

Mass = 0.58 mol × 197 g/mol

Mass = 114.26 g

4 0

3 years ago

Describe the reaction below by listing the

rjkz [21]

Answer:

The covalent bond in Cl₂ is break and combine with sodium to form NaCl through ionic bond.

Explanation:

Chemical equation:

Na + Cl₂ → NaCl

Balanced chemical equation:

2Na + Cl₂ → 2NaCl

The given reaction indicate the formation of sodium chloride.

Sodium chloride is an ionic compound. It is formed by the reaction of chlorine and sodium. The type of bond in Cl₂ is covalent. Both chlorine atoms are tightly held together through sharing of electrons. When sodium chloride is formed the covalent between the chlorine atoms are break and it react with sodium . The chlorine toms thus gain the one electron from the sodium atom and became negative ion while sodium by losing its one valance electrons became positive ions. The strong electrostatic forces are develop between them and ionic bond is formed.

6 0

3 years ago

As ___ increases,___ increases

Goshia [24]

Answer:

if the force applied increases

if the area of contact increases

Explanation:

8 0

2 years ago

Why cant fungi make there own food using photosynthesis

dangina [55]

Fungi cannot make their food from sunlight, water and carbon dioxide as plants do, in the process known as photosynthesis

4 0

3 years ago

Find the pH of a 0.010 M HNO2 solution.

lidiya [134]

Data:
Molar Mass of HNO2
H = 1*1 = 1 amu
N = 1*14 = 14 amu
O = 3*16 = 48 amu
------------------------
Molar Mass of HNO2 = 1 + 14 + 48 = 63 g/mol

M (molarity) = 0.010 M (Mol/L)

Now, since the Molarity and ionization constant has been supplied, we will find the degree of ionization, let us see:
M (molarity) = 0.010 M (Mol/L)
Use: Ka (ionization constant) = $5.0*10^{-4}$
$\alpha^2 (degree\:of\:ionization) = ?$

$Ka = M * \alpha^2$
$5.0*10^{-4} = 0.010* \alpha^2$
$0.010\alpha^2 = 5.0*10^{-4}$
$\alpha^2 = \frac{5.0*10^{-4}}{0.010}$
$\alpha^2\approx500*10^{-4}$

$\alpha\approx\sqrt{500*10^{-4}}$
$\alpha \approx 2.23*10^{-3}$

Now, we will calculate the amount of Hydronium [H3O+] in nitrous acid (HNO2), multiply the acid molarity by the degree of ionization, we will have:

$[ H_{3} O^+] = M* \alpha$
$[ H_{3} O^+] = 0.010* 2.23*10^{-3}$
$[ H_{3} O^+] \approx 0.0223*10^{-3}$
$[ H_{3} O^+] \approx 2.23*10^{-5} \:mol/L$

And finally, we will use the data found and put in the logarithmic equation of the PH, thus:

Data:
log10(2.23) ≈ 0.34
pH = ?
$[ H_{3} O^+] = 2.23*10^{-5}$

Formula:
$pH = - log[H_{3} O^+]$

Solving:
$pH = - log[H_{3} O^+]$
$pH = -log2.23*10^{-5}$
$pH = 5 - log2.23$
$pH = 5 - 0.34$
$\boxed{\boxed{pH = 4.66}}\end{array}}\qquad\quad\checkmark$

Note:. The pH <7, then we have an acidic solution.

6 0

3 years ago