Question

How do we find the number of neutrons in an atom?%0D%0A*%0D%0A1 point%0D%0AAdd the atomic number and mass number together%0D%0ASubtract the number of electrons from the number of protons%0D%0ASubtract the number of protons from the mass number
Answer
Which of the following does the atomic number of an atom or element represent?
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1 point
The number of protons in the atom
The number of neutrons in the atom
The number of particles in the nucleus of the atom
Answer
A molecule of ethanol has two carbon atoms, six hydrogen atoms, and one oxygen atom. A ball-and-stick model of a molecule of ethanol is made from the following components:

one red ball
two black balls
six white balls
eight sticks

What do the white balls in this model represent?
Answer
Which term describes the repeated arrangement of the same molecule?
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1 point
bonds
extended structure
molecular model
Answer
use the periodic table to answer the question.

Which Statement about magnesium [Mg] and calcium [Ca] is correct?
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1 point
Captionless Image
They are both classified as noble gases.
They both have the same number of valence electrons.
They both have the same number of electron shells.
Answer
What property do elements in group 18 [or 8] most likely share?
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1 point
They are silver in color.
They are malleable.
They have low or no reactivity.
Answered by GPT-4o mini
To find the number of neutrons in an atom, you should **subtract the number of protons from the mass number**.

The mass number is the total number of protons and neutrons in the nucleus of an atom, while the atomic number (which is equal to the number of protons) indicates the element. Therefore, the formula to find the number of neutrons is:

**Number of Neutrons = Mass Number - Atomic Number (Number of Protons)**

So, the correct answer is: **Subtract the number of protons from the mass number.**
Answered by GPT-4o mini
The atomic number of an atom or element represents **the number of protons in the atom**.

Thus, the correct answer is: **The number of protons in the atom.**
Answered by GPT-4o mini
In a ball-and-stick model of a molecule of ethanol (C₂H₆O), the white balls represent hydrogen atoms.

To clarify:
- The **black balls** represent carbon atoms (2 carbon atoms in ethanol).
- The **red ball** represents the oxygen atom (1 oxygen atom in ethanol).
- The **white balls** represent the hydrogen atoms (6 hydrogen atoms in ethanol).

So, in this context, the white balls are used to symbolize the hydrogen atoms in the ethanol molecule.
Answered by GPT-4o mini
The term that describes the repeated arrangement of the same molecule is **extended structure**.

An extended structure refers to a larger, repeating framework made up of the same molecular units, often seen in crystalline solids or polymers.

So, the correct answer is: **extended structure.**
Answered by GPT-4o mini
To evaluate the statements about magnesium (Mg) and calcium (Ca):

1. **They are both classified as noble gases.** - This is incorrect, as both magnesium and calcium are classified as alkaline earth metals and not noble gases.

2. **They both have the same number of valence electrons.** - This statement is correct. Both magnesium and calcium are in Group 2 of the periodic table, which means they each have 2 valence electrons.

3. **They both have the same number of electron shells.** - This statement is incorrect. Magnesium (atomic number 12) has 3 electron shells, while calcium (atomic number 20) has 4 electron shells.

Thus, the correct answer is: **They both have the same number of valence electrons.**
Answered by GPT-4o mini
Elements in Group 18 of the periodic table, also known as the noble gases, most likely share the property of **having low or no reactivity**.

Noble gases, such as helium, neon, argon, krypton, xenon, and radon, are known for their lack of chemical reactivity under standard conditions due to their complete valence electron shells.

Thus, the correct answer is: **They have low or no reactivity.**