Answer:
104.969 amu.
Explanation:
From the question given above, the following data were obtained:
Isotope A:
Mass of A = 107.977 amu
Abundance (A%) = 0.1620%
Isotope B:
Mass of B = 106.976 amu
Abundance (B%) = 1.568%
Isotope C:
Mass of C = 105.974 amu
Abundance (C%) = 47.14%
Isotope D:
Mass of D = 103.973 amu
Abundance (D%) = 51.13%
Average atomic mass =?
The average atomic mass of the element can be obtained as follow:
Average atomic mass = [(Mass of A × A%) /100] + [(Mass of B × B%) /100] + [(Mass of C × C%) /100] + [(Mass of D × D%) /100]
Average atomic mass = [(107.977 × 0.1620)/100] + [(106.976 × 1.568)/100] + [(105.974 × 47.14)/100] + [(103.973 × 51.13)/100]
= 0.175 + 1.677 + 49.956 + 53.161
= 104.969 amu
Therefore, the average atomic mass of the element is 104.969 amu.
Explanation:
It is known that in a simple cubic unit cell the atoms are only present at the corner of the unit cell. This means that there are in total 8 atoms present in a simple cubic unit cell.
Therefore, in one simple cubic unit cell sharing of one atom is only 
.
Hence, the total number of atoms in a unit cell will be as follows.
= 1
Thus, we can conclude that there is 1 calcium atom present in each unit cell.
I'm assuming that C is carbon.
55.1259 g of C
Answer:
0.486atm is the pressure of the cylinder
Explanation:
1 mole of Pb(NO₃)₂ descomposes in 4 moles of NO2 and 1 mole of O2. That is 1 mole descomposes in 5 moles of gas.
To find the pressure of the cylinder, we need to find moles of gas produced, and using general gas law we can determine the pressure of the gas:
<em>Moles Pb(NO₃)₂ and moles of gas:</em>
3.31g * (1mol / 331g) = 0.01 moles of Pb(NO₃)₂.
That means moles of gas produced is 0.05 moles.
<em>Pressure of the gas:</em>
Using PV = nRT
P = nRT/V
<em>Where P is pressure (Incognite)</em>
<em>V is volume (2.53L)</em>
<em>R is gas constant (0.082atmL/molK)</em>
<em>T is absolute temperature (300K)</em>
And n are moles of gas (0.05 moles)
P = 0.05mol*0.082atmL/molK*300K / 2.53L
P = 0.486atm is the pressure of the cylinder
Answer:
1. No 1 looks like a statement and not a question.
2.Ionic compounds are usually formed from the transfer of electrons from metals to Non metals. All others are Ionic compounds except HCl(Its a covalent compound).
3. The Formula would be K2S. Exchange of Radicals takes place. Sulphur has a -2 charge and potassium has a +1 charge. when they both exchange radicals... The compound is K2S.
4.Group 1 elements have only 1 electron in their outermost shell.
5. its charge will be +1 because it loses the 1 electron in its outermost shell.
6.Group 2 elements have 2electrons in their Valence shell.
7.Already answered. same as No 5.
8. Group 16;Also known as group 6. They have only 6 electrons in their outermost shell.
9.When they want to become stable... they acquire 2electrons to complete their octet... so they possess a -2 charge by forming an ion.
10. i)They form ions when Dissolve in solutions
ii) They are hard and brittle
iii) They have high boiling points
