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1 year ago

A sample has an atomic number is 18 and atomic mass 33, what is the number of neutrons?

Chemistry

1 answer:

Ivenika [448]1 year ago

3 0

Answer:

15 neutrons

Explanation:

the atomic mass shows the amount of neutrons and protons added together

the atomic number shows us how many protons they are (you can also find out how many electrons a element has by looking at its atomic number as it will have the same amount of protons)

so to find the amount of neutrons the sample has you have you subtract the atomic number which is the amount of protons from the mass number which tells us the amount of neutrons and protons added together but we only need the neutrons that's why we subtract it

33-18=15

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What is the relationship between frequency and wavelength?

IrinaVladis [17]

Answer:

frequency it the measure of the wave length. The measure of the peaks and troughs is how you measure the frequency. the distance between these is the wave length.

6 0

2 years ago

A mixture of krypton and argon gas is expanded from a volume of 88.0L to a volume of 100.0L, while the pressure is held constant

Firlakuza [10]

Answer:

-3.28 × 10⁴ J

Explanation:

Step 1: Given data

Pressure exerted (P): 27.0 atm

Initial volume (Vi): 88.0 L

Final volume (Vf): 100.0 L

Step 2: Calculate the work (w) done by the gaseous mixture

We will use the following expression.

w = -P × ΔV = -P × (Vf - Vi)

w = -27.0 atm × (100.0 L - 88.0 L)

w = -324 atm.L

Step 3: Convert w to Joule (SI unit)

We will use the conversion factor 1 atm.L = 101.325 J.

-324 atm.L × 101.325 J/1 atm.L = -3.28 × 10⁴ J

5 0

2 years ago

Carbordum is silicon carbide SiC a very hard material used as an abrasive on sand paper and in other applications. it is prepare

AleksandrR [38]

Answer:

4.5 kilograms of silicon dioxide is required to produce 3.00 kg of SiC.

Explanation:

The balanced equation for the reaction between silicon dioxide and carbon at high temperature is given as:

$SiO_2+3C\rightarrow SiC+2CO$

1 mole silicon dioxide reacts with 3 moles of carbon to give 1 moles of silicon carbide and 2 moles of carbon monoxide.

Mass of SiC = 3.00kg = 3000.00 g

1 kg = 1000 g

Molecular mass of SiC = 40 g/mol

Moles of SiC = $\frac{3000.00 g}{40 g/mol}= 75 mol$

According to reaction, 1 mole of SiC is produced from 1 mole of silicon dioxide.

Then 75 moles of SiC will be produce from:

$\frac{1}{1}\times 75 mol=75 mol$ of silicon dioxide.

mass of 75 moles of silicon dioxde:

$75 mol\times 60 g/mol=4500 g=4.5 kg$

4.5 kilograms of silicon dioxide is required to produce 3.00 kg of SiC.

3 0

3 years ago

predict the product that forms in the synthesis reaction between potassium metal and iodine gas. provide the balanced chemical e

Doss [256]

K + I - > KI
Potassium (needs to lose 1 electron) responds with Iodine (needs to pick up 1 electron) to fulfill both component's octet, shaping a salt, potassium iodide
This is a similar case for NaCl, simply unique components. Trust this made a difference.

5 0

3 years ago

Read 2 more answers

Equation balancing

meriva

Answer:

For a: The balanced equation is $2S(s)+3O_2(g)\rightarrow 2SO_3(g)$

For c: The balanced equation is $2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)$

Explanation:

A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.