The question is incomplete; the complete question is;
A chemist must dilute 99.4 mL of 152 mM aqueous potassium dichromate (K_2Cr_2O_7) solution until the concentration falls to 55.0 mM He'll do this by adding distilled water to the solution until it reaches a certain final volume. Calculate this final volume, in liters. Be sure your answer has the correct number of significant digits.
Answer:
0.275 L
Explanation:
From C1V1 = C2V2
Where;
C1= initial concentration of the solution 152 × 10^-3 M
V1= initial volume of the solution = 99.4 × 10^-3 L
C2 = concentration after dilution = 55 × 10^-3 M
V2 = volume after dilution = the unknown
V2 = C1 V1/C2
V2 = 152 × 10^-3 × 99.4 × 10^-3 / 55 × 10^-3
V2 = 0.275 L
Answer:
B
Explanation:
When work is done, energy is transferred between systems, or transformed from one type of energy into another type. Energy shares the same units of measure as work.
Use the formula PV=NRT to find the amount of moles of nitrogen gas. Then use the same formula using the amount of moles found to find the temperature
Answer:
The percentage composition of each element in H2O2 is 5.88% H and 94.12% O (Option D).
Explanation:
Step 1: Data given
Molar mass of H = 1.0 g/mol
Molar mass of O = 16 g/mol
Molar mass of H2O2 = 2*1.0 + 2*16 = 34.0 g/mol
Step 2: Calculate % hydrogen
% Hydrogen = ((2*1.0) / 34.0) * 100 %
% hydrogen = 5.88 %
Step 3: Calculate % oxygen
% Oxygen = ((2*16)/34)
% oxygen = 94.12 %
We can control this by the following equation
100 % - 5.88 % = 94.12 %
The percentage composition of each element in H2O2 is 5.88% H and 94.12% O (Option D).
Answer:
Molecular formula = C₄H₆As₆Cu₄O₁₆
Explanation:
Given data:
Empirical formula = C₂H₃As₃Cu₂O₈
Molar mass of compound = 1013 g/mol
Molecular formula = ?
Solution:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
Empirical formula mass of C₂H₃As₃Cu₂O₈ is 506.897 g/mol
by putting values.
n = 1013 / 506.897
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 (C₂H₃As₃Cu₂O₈)
Molecular formula = C₄H₆As₆Cu₄O₁₆
