Question

question 10 (1 point)
to what category of elements does an element belong if it is a poor conductor of electricity?
metalloids
transition elements
nonmetals
metals
question 11 (1 point)
in which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correct
in, 49 protons, 49 electrons
cs, 55 protons, 132.9 electrons
f, 19 protons, 19 electrons
zn, 30 protons, 60 electrons
question 12 (1 point)
the atomic number of an element is the total number of which particles in the nucleus?
electrons
protons and electrons
neutrons
protons
question 13 (2 points)
what element has the electron configuration 1s²2s²2p⁶3s²3p²?

Explanation:

Question 10

Metals are good conductors of electricity. Metalloids have intermediate conductivity. Transition elements (metals) are good conductors. Non - metals are poor conductors as they lack free - moving electrons for electrical conduction.

• For a neutral atom, the number of protons = number of electrons.
• In (Indium) has an atomic number of 49, so 49 protons and 49 electrons (neutral atom).
• Cs (Cesium) has an atomic number of 55, so 55 protons and 55 electrons (not 132.9 which is a non - integer and not a valid number of electrons).
• F (Fluorine) has an atomic number of 9 (not 19).
• Zn (Zinc) has an atomic number of 30, so 30 protons and 30 electrons (not 60).

The atomic number of an element is defined as the number of protons in the nucleus of an atom. Electrons are outside the nucleus. Neutrons do not define the atomic number. Protons and electrons (where electrons are outside the nucleus) also do not define the atomic number.

Answer:

C. nonmetals

Question 11