Which body system does rheumatoid arthritis affect?

I think it's nervous system because it's mainly pain in the joints but it could be muscular because it might limit your movement

answer; //the above statement is (false);

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds