All categories

3 years ago

When radium-226 (atomic number-88) decays by emitting an alpha particle it becomes _____.

Chemistry

1 answer:

topjm [15]3 years ago

3 0

Answer:

d. Radon-222

Explanation:

²²⁶₈₈Ra → ²²²₈₆Rn + ⁴₂He

Alpha particle is a helium nucleus with mass number 4 and atomic number 2. According to the law of conversation of mass, the sum of the mass number and atomic number must be equal on both side of the reaction.

Since the mass number of Ra is 226 and that of He is 4. The mass number of the unknown element must be 226 - 4 = 222.

Since the atomic number of Ra is 88 and that of He is 2. The atomic number of the unknown element must be 88 - 2 = 86.

Now looking in the periodic table Radon is the only element with atomic number 86.

You might be interested in

If a reaction is reversible what are the relative amounts of reactant and product

Alina [70]

<span>If a reaction is reversible, then it will attain the phase of Equilibrium and at that phase, the Amount of Reactants and Products would be: Equal

Hope this helps!</span>

3 0

3 years ago

Read 2 more answers

A chemist dissolves 867. mg of pure barium hydroxide in enough water to make up 170. mL of solution. Calculate the pH of the sol

Ilya [14]

Answer: The pH of the solution is 11.2

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n = moles of solute

$V_s$ = volume of solution in ml

moles of $Ba(OH)_2$ = $\frac{\text {given mass}}{\text {Molar mass}}=\frac{0.867g}{171g/mol}=0.00507mol$ (1g=1000mg)

Now put all the given values in the formula of molality, we get

$Molarity=\frac{0.00507\times 1000}{170}$

$Molarity=0.0298$

pH or pOH is the measure of acidity or alkalinity of a solution.

pH is calculated by taking negative logarithm of hydrogen ion concentration.

$pOH=-\log [OH^-]$

$Ba(OH)_2\rightarrow Ba^{2+}+2OH^{-}$

According to stoichiometry,

1 mole of $Ba(OH)_2$ gives 2 mole of $OH^-$

Thus 0.0298 moles of $Ba(OH)_2$ gives = $\frac{2}{1}\times 0.0298=0.0596$ moles of $OH^-$

Putting in the values:

$pOH=-\log[0.0596]=2.82$

$pH+pOH=14$

$pH=14-2.82$

$pH=11.2$

Thus the pH of the solution is 11.2

8 0

3 years ago

Soda water is water that has bubbles of carbon dioxide in it,

Elan Coil [88]

Answer:

I think mixture

Explanation:

Mixture because it is a mixture of water and carbon

3 0

3 years ago

Read 2 more answers

Of the below gases, which would deviate most from ideal gas behavior? CO O2 NH3 SF4

Vlad [161]

Answer:

For gases such as hydrogen, oxygen, nitrogen, helium, or neon, deviations from the ideal gas law are less than 0.1 percent at room temperature and atmospheric pressure. Other gases, such as carbon dioxide or ammonia, have stronger intermolecular forces and consequently greater deviation from ideality.

Explanation:

8 0

3 years ago

Be sure to answer all parts.

Marianna [84]

a)3^2 = 9 times

b)2^2*2 = 8 times

c)(1/2) = half times

7 0

3 years ago