1. The atomic number of an element is determined by the number of:
a. protons.
b. electrons.
C. neutrons.
d. isotopes.

Which element has the lowest electronegativity? calcium(ca) gallium(ga) selenium(se) bromine(br)

Consider the reaction: 2al(s) + fe2o3(s) → al2o3(s) + 2fe(s) the δhf for fe2o3(s) = -824.3 kj/mole. the δhf for al2o3(s) = -1675.7 kj/mole. finish the equation. δhrxn = [(1)( kj/mole) + (2)( kj/mole)] - [(1)( kj/mole) + (2) ( kj/mole)]

An alpha particle is: a hydrogen atom a nucleus of helium two neutrons an electron