Answer:
Group 7A
Explanation:
The group 7A elements consists of the most reactive non-metals on the periodic table.
This group is known as the group of halogens. They consist of element fluorine, chlorine, bromine, iodine and astatine.
- The elements in this group have the highest electronegativity values.
- They have 7 valence electrons and requires just one electron to complete their octets.
- This way, they are highly reactive in their search for that single electron.
Answer: when reactants and products are gases at STP.
Justification:
1) STP stands for standard temperature (0°) and pressure (1 atm).
2) According to the kinetic molecular theory of the gases, and as per Avogadro's principle, equal volumes of gases, at the same temperature and pressure, have the same number of molecules.
3) Since the coefficients in a balanced chemical equation represent number of moles, when reactants and products are gases at the same temperature and pressure, the mole ratios are the same that the volume ratios, and then the coefficients of the chemical equation represent the volume ratios.
Answer:(3)
Explanation: 2Al+3H2SO4----->Al(2SO4)3+3H2
B protons are positive atoms and are inside the nucleus
Answer:
0.0000159
Explanation:
Divide 15.9 by 1000000, because 1 kilometer equals 1000000 millimeters.