The average atomic weight of this element can be calculated as follows:
average atomic weight =
(atomic weight of first isotope)(its percentage of abundance) +
(atomic weight of second isotope)(its percentage of abundance)
atomic weight of first isotope = 68.9 amu
its percentage of abundance = 0.604
atomic weight of second isotope = 70.9 amu
its percentage of abundance = 0.396
So, just substitute in the above equation to get the atomic weight of the element as follows:
atomic weight = (68.9)(0.604) + (70.9)(0.396) = 69.692 amu
Answer:
236.8 g
Explanation:
From the reaction equation;
CaC2 + 2H2O(I) --------> C2H2(g) + Ca(OH)2(aq)
Since;
1 mole of CaC2 yields 1 mole of Ca(OH)2
It follows that 3.20 moles of CaC2 also yields 3.2 moles of Ca(OH)2
Mass of Ca(OH)2 = number of moles * molar mass
molar mass of Ca(OH)2 = 74 g/mol
Mass of Ca(OH)2 = 3.20 moles * 74 g/mol =
Mass of Ca(OH)2 = 236.8 g
WHat? May you please rephrase your question? I think you meant in an organic compound? The answer to that would be CARBON.
The hydrogen ion concentration, [H ], in the solution of phenol red solution of pH 11.20 is 6.3 X 
moles/litre.
Explanation:
Data given:
basic solution of phenol red is given as it has pH of 11.2
hydrogen ion concentration = ?
the hydrogen ion concentration is calculated by using the following formula:
pH = -
[
]
Rearranging the equation:
[] = 
Putting the values in the above equation:
[] = 
[] = 6.3 X moles/litre
The hydrogen ion concentration is very small and the solution of phenol red is basic in nature. The pH of 11.2 also indicates that solution is basic and teh color of the solution is bright pink.
