Answer:
The concentration of chloride ions in the final solution is 3 M.
Explanation:
The number of moles present in a solution can be calculated as follows:
number of moles = concentration in molarity * volume
In 100 ml of a 2 M KCl solution, there will be (0.1 l * 2mol/l) 0.2 mol Cl⁻
For every mol of CaCl₂, there are 2 moles of Cl⁻, then, the number of moles of Cl⁻ in 50 l of a 1.5 M solution will be:
number of moles of Cl⁻ = 2 * number of moles of CaCl₂
number of moles of Cl⁻ = 2 ( 50 l * 1.5 mol / l ) = 150 mol Cl⁻
The total number of moles of Cl⁻ present in the solution will be (150 mol + 0.2 mol ) 150.2 mol.
Assuming ideal behavior, the volume of the final solution will be ( 50 l + 0.1 l) 50.1 l. The molar concentration of chloride ions will be:
Concentration = number of moles of Cl⁻ / volume
Concentration = 150.2 mol / 50.1 l = 3.0 M
Answer:
The correct order it b. always add acid last.
Explanation:
Adding acid first could result on a violent reaction and heat or fumes can be generated. The best approach is to always add all the water or non-acid component first, or add a significant portion before adding the acid slowly to the mixture.
Answer:
Coefficients
Explanation:
Chemical equations are first written as a skeleton equation, which includes how many atoms each element and compound has. Skeleton equations are not 'balanced' because the number of atoms of each element on the left side (reactants) is not equal to the right side (products).
To balance a chemical equation, you can write coefficients in front of single elements and compounds. The coefficient multiplies with each single element and with each element in the compound.
For example, in this skeleton equation:
H₂ + Cl₂ => HCl
Reactants: Products:
2 hydrogen 1 hydrogen
2 chlorine 1 chlorine
Write the coefficient 2 in the products.
H₂ + Cl₂ => 2HCl
Now both reactant and product sides have 2 chlorine and 2 hydrogen, so the equation is balanced.
I would say D. Let me know if i am wrong.
