A. Heat is released, so the reaction is <u>exothermic</u>.
B. Heat is absorbed, so the reaction is <u>endothermic</u>.
C. Heat is released, so the reaction is <u>exothermic</u>.
Answer:
The alloys used to make coins are usually Copper, Zinc and Nickel. There are several reasons: The alloy must be very hard to withstand the use and circulation of the coin to not wear out soon. Then, the alloy must have a value less than the value of the currency to avoid that are founded and sold as mere metals.
Explanation:
Answer:
1.62 × 10²⁴ atoms are in 52.3 g of lithium hypochlorite.
Explanation:
To find the amount of atoms that are in 52.3 g of lithium hypochlorite, we must first find the amount of moles. We do this by dividing by the molar mass of lithium hypochlorite.
52.3 g ÷ 58.4 g/mol = 0.896 mol
Next we must find the amount of formula units, we do this be multiplying by Avagadro's number.
0.896 mol × 6.02 × 10²³ = 5.39 × 10²³ f.u.
Now to get the amount of atoms we can multiply the amount of formula units by the amout of atoms in one formula unit.
5.39 × 10²³ f.u. × 3 atom/f.u. = 1.62 × 10²⁴ atoms
1.62 × 10²⁴ atoms are in 52.3 g of lithium hypochlorite.
Answer:
Outer shell is full
Explanation:
The elements represented by the group D are noble gases.
Noble gases have fully filled outer electronic configuration.
He=
Ne=
Ar=
Kr=
...
Answer:
When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level. The energy of the photon is the exact energy that is lost by the electron moving to its lower energy level.
