Which row correctly describes a medical use and an industrial use of radioactive isotopes?
Medical
Industrial
A
Cancer treatment
Coal stations
Power stations
с
Sterilising medical
equipment
Skin products
Sterilising medical
equipment
Radioactive dating
D
Extraction of crude oil

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17