Which pair of symbols represents nuclei with the same number of neutrons? A. 56 Co and 580
B. 57Co and 58Ni
c. 57Fe and 58 Ni
D. 57Mn and 57Fe

B

Explanation:

Mass number  = number of neutrons + number of protons

Atomic number is the number of protons in the nucleus.  

58Ni   : 58 is the number of neutrons + number of protons

atomic number of Ni is 28.  Thus,  58 -28 = 30 neutrons

57Co ;  57 is the number of neutrons + number of protons

number of Co is 27. Thus, 57 – 27  = 30 neutrons

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?