Answer:
If the mass stays constant the object's density decreases as the volume increases. ... Because the property of density is a constant for all variables, density can be used to identify the material an object is made of.
Explanation:
For 7A(17) :
Electronic configuration 
So, there are 5 unpaired electrons present in group 7A(17).
<h3>
What are Unpaired Electrons?</h3>
- An unpaired electron is an electron that doesn't form part of an electron pair when it occupies an atom's orbital in chemistry.
- Each of an atom's three atomic orbitals, designated by the quantum numbers n, l, and m, has the capacity to hold a pair of two electrons with opposing spins.
- Unpaired electrons are extremely uncommon in chemistry because an object carrying an unpaired electron is typically quite reactive. This is because the production of electron pairs, whether in the form of a chemical bond or as a lone pair, is frequently energetically advantageous.
- They play a crucial role in describing reaction pathways even though they normally only appear momentarily during a reaction on a thing called a radical in organic chemistry.
To learn more about unpaired electrons with the given link
brainly.com/question/14356000
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They are examples of elements.
Yes because of the gas combination.
The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and bronchioles. Blood moves in and out of the lungs through the pulmonary arteries and veins that connect to the heart