The scientist that came up with the idea of natural selection was Charles Darwin.
C , the potential energy of a 500kg boulder
Explanation:
Never smoke near a place where hydrogen is generated or being used. Remove all possible sources of flame and sparks. Hydrogen should only be generated and used in a well ventilated out door area. Precautions must be taken to remove all possibilities of fire or explosion.
Answer:
moles Na = 0.1114 g / 22.9898 g/mol=0.004846
moles Tc = 0.4562g /98.9063 g/mol=0.004612
mass O = 0.8961 - ( 0.1114 + 0.4562)=03285 g
moles O = 0.3285 g/ 15.999 g/mol=0.02053
divide by the smallest
0.02053/ 0.004612 =4.45 => O
0.004846/ 0.004612 = 1.0 => Tc
to get whole numbers multiply by 2
Na2Tc2O 9
Explanation:
Hope it right hope it helps
The atom that has 7 valence electrons is A. fluorine.
It is in the halogens group.
It needs 1 more electron to become stable, therefore, it is highly reactive.
