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3 years ago

How many neutrons does element X have if its atomic number is 30 and its mass number is 70?

1 answer:

3 0

The answer is 40.

We can solve this by finding out the number of protons, and neutrons. Atomic number of an element means the number of protons in that element. So, the atom has 30 protons if the atomic number is 30.

On the other hand, mass number is the total number of protons and neutrons, but not electrons, because they're too light comparing to the other 2. Therefore, we can simply solve the number of neutrons in the atom by subtracting the number of protons from the mass number. 70 - 30 = 40.

Therfore, the number of neutrons is 40.

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A measure of the kinetic energy of particle motion within a substance is temperature.

Alchen [17]

True. You're welcome!

3 0

3 years ago

Starting with 6.3 g of salicylic acid, how many grams of acetylsalicylic acid (theoretical yield) can be made? Assume salicylic

tensa zangetsu [6.8K]

Answer:

We will produce 8.2 grams of acetylsalicylic acid

Explanation:

step 1: Data given

Mass of salicylic acid, = 6.3 grams

Molar mass salicylic acid = 138.12 g/mol

Molar mass of acetylsalicylic acid = 180.158 g/mol

Step 2: The balanced equation

C7H6O3 + C4H6O3 → C9H8O4 + C2H4O2

Step 3: Calculate moles salicylic acid

Moles salicylic acid = mass salicylic acid / molar mass salicylic acid

Moles salicylic acid = 6.3 grams / 138.12 g/mol

Moles salicylic acid = 0.0456 moles

Step 4: Calculate moles acetylsalicylic acid

Since the mole ratio is 1 to 1

For 0.0456 moles salicylic acid we'll have 0.0456 moles acetylsalicylic acid

Step 5: Calculate mass acetylsalicylic acid

MAss acetylsalicylic acid = moles acetylsalicylic acid * molar mass acetylsalicylic acid

MAss acetylsalicylic acid = 0.0456 moles * 180.158 g/mol

Mass acetylsalicylic acid = 8.2 grams

We will produce 8.2 grams of acetylsalicylic acid

4 0

3 years ago

Time zones were adopted to fix what problem

morpeh [17]

Time Zones were adopted to fix the time. Without the time zone, you will never know what time it is

8 0

3 years ago

Read 2 more answers

Which is a genotype?

Pani-rosa [81]

Answer:

Genotypes are related with the collection of genes expressed in the DNA.

Explanation:

Hello,

In genetics, two specific terms define the characteristics of a living thing; a genotype and a phenotype; thus, phenotypes are related with the physical manifestation of genes, for instance, red hair, blue eyes, long arms and others.

On the other hand, genotypes are related with the collection of genes expressed in the DNA, and they could be for equal alleles or for different alleles, in other words, it is the version of DNA the living thing has.

Regards.

8 0

3 years ago

In the reaction 2Na + Cl2 → 2NaCl, the products are

Lisa [10]

During a reaction, there are reactants and products. Reactants are the elements that are being added. Products are the result of the reactants.

2Na + Cl2 are the reactants.

2NaCl is the Product.

I hope this helps!

8 0

3 years ago