Answer:
b
Explanation:
b because it's a physical change
Answer:
This can be solved using Dalton's Law of Partial pressures. This law states that the total pressure exerted by a gas mixture is equal to the sum of the partial pressure of each gas in the mixture as if it exist alone in a container. In order to solve, we need the partial pressures of the gases given. Calculations are as follows:
Explanation:
P = 3.00 atm + 2.80 atm + 0.25 atm + 0.15 atm
P = 6.8 atm
3.5 atm = x (6.8 atm)
x = 0.51
Answer:
There are 2.5 * 10^22 beryllium atoms in 0.37 grams
Explanation:
Step 1: Data given
The mass of an atom of beryllium is 1.5 x 10^-26 kg.
Total mass = 0.37 grams
Step 2: Calculate number of atoms
1 atom = 1.5 * 10 ^-26 kg
X atoms = 0.00037 kg
X = 0.00037/1.5*10^-26
X = 2.467 * 10^22 atoms ≈ 2.5 * 10^22 atoms
There are 2.5 * 10^22 beryllium atoms in 0.37 grams
The location of the valence electron or the outermost electron is expressed in quantum numbers. There are five quantum numbers: prinicipal (n), angular momentum (l), magnetic (ms) and magnetic spin (ms) quantum numbers. This is based on Bohr's atomic model where electrons orbit around the nucleus. These electrons are in the orbitals with specific energy levels. Starting from energy level 1 that is closest to the nucleus, the energy level decreases to 2, 3, 4, 5, 6, and 7. These energy level numbers represent the principal quantum number. Within each orbital also contains subshell. From increasing to decreasing order, these subshells are the s, p, d and f subshells. These subshells represent the angular momentum quantum numer. Specifically, s=0, p=1, d=2 and f=3. Therefore, if the electron is in the orbital 5p, the quantum number would be: 5, 1. Applying these to the choices, the correct pairing would be:
2p: n=2. l=1
3d: n=3, l=2
2s: n=2. l=0
4f: n=4. l=3
1s: n=1, l=0
