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3 years ago

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Chemistry

1 answer:

Ahat [919]3 years ago

3 0

Answer:

$KClO_3$

Explanation:

Hello!

In this case, as we know the mass of the total sample, we can first compute the mass of oxygen:

$m_O=22.9g-7.33g-6.65g=8.92g$

Next, we compute the moles of each element:

$n_K=\frac{7.33g}{39.9g/mol}= 0.184mol\\\\n_{Cl}=\frac{6.65g}{35.45g/mol}=0.188mol \\\\n_O=\frac{8.92g}{16.00g/mol} =0.5575mol$

Now, we divide the moles by 0.184 moles, the fewest ones, to obtain:

$K=\frac{0.184}{0.184}=1.0 \\\\Cl=\frac{0.187}{0.184}=1.0\\\\O=\frac{0.5575}{0.184} =3.0$

Therefore, the empirical formula is:

$KClO_3$

Regards!

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The nuclear fission process releases neutrons and Question 27 options: alpha particles electrons energy beta particles

Brut [27]

Answer: Option (c) is the correct answer.

Explanation:

Nuclear fission is a reaction in which a heavy nucleus when bombards with a neutron(s) then it results in the formation of neutrons along with smaller nuclei of equivalent size and magnitude and emission of energy.

Thus, we can conclude that out of the given options, the nuclear fission process releases neutrons and energy.

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3 years ago

What is the intensity in W/m2 of a laser beam used to burn away cancerous tissue that, when 91.0% absorbed, puts 540 J of energy

Gekata [30.6K]

Answer:

2.3x10⁷ W/m²

Explanation:

The intensity (I) of a laser is its potency (P) divided by the area (A) that it is affected. The potency is the energy applied (or absorbed) in a period, thus id 91.0% of the energy is absorbed, so:

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And,

P = E/t, where t is the time in seconds

P = 491.4/4.00

P = 122.85 J/s

P = 122.85 W

The are of a circular spot is:

A = (π/4)*d²

Where d is the diameter. Thus, with d = 2.60 mm = 0.0026 m

A = (π/4)*(0.0026)²

A = 5.31x10⁻⁶ m²

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4 years ago

Complete and balance the reaction in acidic solution. equation: ZnS + NO_{3}^{-} -> Zn^{2+} + S + NO ZnS+NO−3⟶Zn2++S+NO Which

kotykmax [81]

Answer:

Balanced reaction: $3ZnS+2NO_{3}^{-}+8H^{+}\rightarrow 3Zn^{2+}+3S+2NO+4H_{2}O$

S is oxidized and N is reduced.

$NO_{3}^{-}$ is the oxidizing agent and ZnS is the reducing agent.

Explanation:

Reaction: $ZnS+NO_{3}^{-}\rightarrow Zn^{2+}+S+NO$

$\Rightarrow$ Oxidation: $ZnS\rightarrow Zn^{2+}+S$

Balance charge: $ZnS-2e^{-}\rightarrow Zn^{2+}+S$ ...............(1)

$\Rightarrow$ Reduction: $NO_{3}^{-}\rightarrow NO$

Balance H and O in acidic medium : $NO_{3}^{-}+4H^{+}\rightarrow NO+2H_{2}O$

Balance charge: $NO_{3}^{-}+4H^{+}+3e^{-}\rightarrow NO+2H_{2}O$ ...............(2)

[ $3\times$ Equation-(1)] + [ $2\times$ Equation-(2)]:

$3ZnS+2NO_{3}^{-}+8H^{+}\rightarrow 3Zn^{2+}+3S+2NO+4H_{2}O$

Oxidation number of S increases from (-2) to (0) for the conversion of ZnS to S. Therefore S is oxidized.

Oxidation number of N decreases from (+5) to (+2) for the conversion of $NO_{3}^{-}$ to NO. Therefore N is reduced.

$NO_{3}^{-}$ consumes electron from ZnS. Therefore $NO_{3}^{-}$ is the oxidizing agent and ZnS is the reducing agent.

7 0

4 years ago

If 44.7 g of KCI (MM = 74.55 g/mol) are added to a 500.0 mL volumetric flask, and water is added to fill the flask, what is the

navik [9.2K]

1.199 M is the concentration of KCI in the resulting solution.

<h3 /><h3>What are moles?</h3>

A mole is defined as 6.02214076 × $10^{23}$ of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.

No.of moles of KCI

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$Moles = \frac{44.7 g}{74.5513 g/mol}$

= 0.599 moles

Vol.of the solution,V= 500 ml

= 0.5 liter

Molarity

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$Molality = \frac{0.599 moles}{0.5 liter}$

= 1.199 M

Hence, 1.199 M is the concentration of KCI in the resulting solution.

Learn more about moles here:

brainly.com/question/8455949

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2 years ago

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4 years ago