<span>Answer : The average atomic mass of rubidium = 85.468
Explanation: Given that 85Rb isotope has atomic mass of 84.912amu with abundance of 72.17%
therefore we get 84.912 x 0.7217 = 61.281
and 87Rb isotope has atomic mass of 86.909 with abundance of 27.83%
hence we get 86.909 x 0.2783 = 24.187
Thus we get 61.281 + 24.187 = 85.468 as the average atomic mass of Rubidium.</span>
It's decomposition
A combustion reaction involves carbon dioxide so it can't be that
The water is not being formed
The water is not replaced by the other molecules
So it is decomposition, not just from process of elimination, but also because decomposing water means heating it.
<h3>
Answer:</h3>
482.596 grams
<h3>
Explanation:</h3>
The relationship between moles, molar mass and mass of a compound is given by;

In this case;
The compound in question is P₂O₅
Molar mass of P₂O₅ = 141.94 g/mol
Rearranging the formula;
Mass = Moles × molar mass
Therefore;
Mass of P₂O₅ = 3.4 mol × 141.94 g/mol
= 482.596 grams
Therefore, mass of P₂O₅ is 482.596 grams
6.069 grams is the mass of hydrogen formed when 27 g of aluminum reacts with excess hydrochloric acid.
Explanation:
Balanced equation for the reaction:
2 Al + 6 HCl → 2 AlCl₃ + 3 H₂
data given:
mass of aluminum = 27 grams
atomic mass of one mole of aluminum = 26.89 grams/mole
formula to calculate number of moles:
number of moles = 
number of moles = 
= 1.004 moles of aluminum will react
from the balanced equation:
2 moles of Al reacted to form 3 moles of H2
1.004 moles of Al will produce x moles of H2
= 
x = 3.012 moles of H2 will be formed.
mass will be calculated as number of moles multiplied by atomic weight
mass of 3.012 moles of hydrogen ?(atomic weight of one mole H2 = 2.015 grams)
= 3.012 x 2.015
= 6.069 grams of H2 will be formed.
Answer:
a = 4
b = 3
Explanation:
<u>SOLUTION :-</u>
Balance it by using 'hit & trial' method , and you'll get the answer :-
2Fe₂O + 3C → <u>4</u>Fe + <u>3</u>CO₂
⇒ a = 4 ; b = 3
<u></u>
<u>VERIFICATION :-</u>
<em>In reactant side of equation :-</em>
- Number of atoms in Fe = 2×2 = 4
- Number of atoms in O = 2×3 = 6
- Number of atoms in C = 3×1 = 3
<em>In product side of equation :-</em>
- Number of atoms in Fe = 4×1 = 4
- Number of atoms in C = 3×1 = 3
- Number of atoms in O = 3×2 = 6
Number of atoms of each element is equal in both reactant & product side of equation. Hence , the equation is balanced.