Answer: The complete nuclear symbol will be 
Explanation:
The nuclear symbol is written as: 
where Z= atomic number , A = mass number X = symbol of element
Atomic number is defined as the number of protons or number of electrons that are present in an atom.
For an electrically neutral atom,
Atomic number = Number of electrons = Number of protons = 8
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
Mass number = 8 + 10 = 18
Thus complete symbol will be
Answer: Time taken by a sound impulse to travel through an aluminum rod 25 kilometers long is 4.9 seconds.
Solution:
Length of aluminium rod = 25 km = 25000 m (1 km=1000 m)
Time taken by sound to travel through aluminium = 5100 m/s (from the table given)
time taken =
Hence, the correct option is 4.9 seconds.
NaHCO3 = 22.99 + 1.008 + 16(3) = 83.99 g/mol
Na = 22.99g/83.99 g weight of molecule =.2727 or 27.27%
3.0 g* .2727 = 0.8211 grams of sodium in sample of NaHCO3
0.8211 grams Na + 1.266 grams Cl = 2.087 grams
Depending on what you are doing, virtual, or in school, you can contact your school and you ask them, or you can have your teacher, based on the subject, tutor you.
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