What must be true for a spontaneous reaction in an electrochemical cell?
the overall cell potential must be positive.
the overall cell potential must be negative.
the cathode’s standard reduction potential must be positive.
the cathode’s standard reduction potential must be negative.

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

According to periodic trend, which of the following most likely has the highest ionization energy? kr be ni sc

Imagine that a new planet is discovered with two moons of equal mass: moon a and moon b. the mass of the new planet is greater than the combined mass of its moons. moon a is farther away from the new planet than moon b. what is the planet's gravitational pull on moon a compared to the planet's gravitational pull on moon b? the planet's gravity repels moon a with a greater force than it repels moon b, which is why moon a is farther away. the gravitational pull on moon b is greater than on moon a because moon b is closer to the new planet than moon a. the gravitational pull on moon b is greater than on moon a because moon b is farther away from the new planet than moon a. the gravitational pull on moon a is the same as the gravitational pull on moon b because distance does not affect the planet's gravity.