Answer:
phosphorus.
Explanation:
The atomic number of phosphorus is 15 so the protons will be 15.
Answer:
When the two atoms move towards each other a compound is formed by sharing electron pairs supplied by each of the atoms to enable them have the stable 8 (octet) valency electrons in their outermost shell
Explanation:
The electronic configuration of the given element can be written as follows;
1s²2s²2p⁴
The given electronic configuration is equivalent to that of oxygen, therefore, we have;
The number of electrons in the valence shell = 2 + 4 = 6 electrons
Therefore, each atom requires 2 electrons to complete its 8 (octet) electrons in the outermost shell
When the two atoms move towards each other, they react and combine to form a compound by sharing 4 electrons, 2 from each atom, such that each atom can have an extra 2 electrons in its outermost orbit in the newly formed compound and the stable octet configuration is attained by each of the atoms in the newly formed compound.
Answer:
6.022 × 10²² atoms
Explanation:
Generally 1 mol of any element contains 6.02×10^23 atoms. The number 6.022 × 10²³ is known as Avogadro's number.
Mass of Aluminium = 2.70g
Molar mass = 27g/mol
Number of moles = Mass / Molar mass = 2.70 / 27 = 0.1 mol
1 mol = 6.022 × 10²³
0.1 mol = x
x = 6.022 × 10²³ * 0.1 = 6.022 × 10²² atoms
<span>12.4 g
First, calculate the molar masses by looking up the atomic weights of all involved elements.
Atomic weight manganese = 54.938044
Atomic weight oxygen = 15.999
Atomic weight aluminium = 26.981539
Molar mass MnO2 = 54.938044 + 2 * 15.999 = 86.936044 g/mol
Now determine the number of moles of MnO2 we have
30.0 g / 86.936044 g/mol = 0.345081265 mol
Looking at the balanced equation
3MnO2+4Al→3Mn+2Al2O3
it's obvious that for every 3 moles of MnO2, it takes 4 moles of Al. So
0.345081265 mol / 3 * 4 = 0.460108353 mol
So we need 0.460108353 moles of Al to perform the reaction. Now multiply by the atomic weight of aluminum.
0.460108353 mol * 26.981539 g/mol = 12.41443146 g
Finally, round to 3 significant figures, giving 12.4 g</span>
The percentage error is given by multiplying relative error by 100%.
Therefore, to get the percentage error we need relative error which is given by dividing the absolute error with the actual value.
Absolute error = 0.133
Percentage error = 0.133/5.586 × 100%
= 2.38%
The percentage error is therefore; 2.38%
