A group of students conducted an activity for science class. They used a galvanometer, which is an instrument that can detect an electric current. They followed these steps:
Obtain a 100 foot long electrical extension cord.
Connect each end of the extension cord to the galvanometer.
Using duct tape, secure part of the extension cord to the ground as shown below.
Swing the top part of the extension cord as if a person were to enter to jump rope.
Have a student observe the galvanometer while the cord is rotating.

Students observed that the needle of the galvanometer moves. What does this demonstrate?
A.
Moving an electrical conductor next to an electric current produces a magnetic field.
B.
Moving an electrical conducting wire close to the ground changes Earth's magnetic field.
C.
Moving an electrical conducting wire through a magnetic field changes the wire's conductivity.
D.
Moving an electrical conductor through Earth's magnetic field induces an electric current.

r just means there's a number of carbon in teh chain. for example rcooh means that after x number of carbon, the chain ends with cooh.

explanation:

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i  

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.