(2) Arsenic. It is an element and elements are chemically the simplest units and cannot be broken down by any chemical change.
Answer: 5.66 dm3
Explanation:
Given that:
Volume of neon gas = ?
Temperature T = 35°C
Convert Celsius to Kelvin
(35°C + 273 = 308K)
Pressure P = 0.37 atm
Number of moles N = 0.83 moles
Note that Molar gas constant R is a constant with a value of 0.0082 ATM dm3 K-1 mol-1
Then, apply ideal gas equation
pV = nRT
0.37atm x V = 0.83 moles x 0.0082 atm dm3 K-1 mol-1 x 308K
0.37 atm x V = 2.096 atm dm3
V = (2.096 atm dm3 / 0.37atm)
V = 5.66 dm3
Thus, the volume of the neon gas is 5.66 dm3
Answer:
Concentration of dissolved nitrogen = 5.2 × 10⁻⁴ mol/L
Explanation:
More the pressure of the gas, more will be its solubility.
So, for two different pressure, the relation between them is shown below as:-
Given ,
P₁ = 1 atm
P₂ = 0.76 atm
C₁ = 6.8 × 10⁻⁴ mol/L
C₂ = ?
Using above equation as:
<u>Concentration of dissolved nitrogen = 5.2 × 10⁻⁴ mol/L</u>
Answer:
1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵
Explanation:
1) Ca:
Its atomic number is 20. So it has 20 protons and 20 electrons.
Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.
So, you have two more electrons (20 - 18 = 2) to distribute.
Those two electrons go the the orbital 4s.
Finally, the electron configuration is [Ar] 4s².
2) Pm
The atomic number of Pm is 61, so it has 61 protons and 61 electrons.
Pm is in the row (period) 6. So, the noble gas before Pm is Xe.
The atomic number of Xe is 54.
Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.
The resultant distribution for Pm is: [Xe]6s² 4f⁵.
Explanation:
Silver and Gold belong to a special group of metals known as the native metals. They are found naturally on their own and not in combined form in rocks.
- These metals are found uncombined because they are unreactive.
- They prefer to alloy with themselves.
- Calcium and magnesium on the other hand are reactive metals.
- The unreactivity of these metals makes them uncombined in nature.
