Answer:
Beryllium
Explanation:
Given parameters:
Number of protons = 4
Number of neutrons = 5
Number of electrons = 4
Unknown:
Element = ?
Solution:
To determine an element, the atomic number is the most important identifier.
The atomic number is the number of protons in an atom.
Since the atom here has a proton number of 4, checking on the periodic table, it is Beryllium, Be
I need a picture because I don’t know what this is talking about
Most chemical elements are solid at room temperature. Some elements exist as gases but only two elements, mercury (Hg) and bromine (Br) are liquids at room temperature (approx 25oC). Hope this helped you!
Answer: 83.74L
Explanation:
Temp. = 295K
P = 713torr = 0.938atm
Mass = 2.65g
PV = nRT
V = nRT/PV
n = Mass/Molar mass
Molar mass of Hydrogen gas = 1.00784*2= 2.0156g/mok
n = 2.65/2.0156 = 1.31469mol
V = 1.31469*0.08205*295/0.938
V = 83.74L
The volume = 83.74L
Answer: He spends 29.17 hours per week
Explanation:
1 class = 50mins
7 classes = 7 x 50mins = 350mins
For 5 days in a week, we have
5 x 350mins = 1750mins
Converting to hours, we have
1750 /60 = 29.17 hours