Answer:
98.6 g/mol.
Explanation:
Equation of the reaction
HX + NaOH--> NaX + H2O
Number of moles = molar concentration × volume
= 0.095 × 0.03
= 0.00285 moles
By stoichiometry, 1 mole of HX reacted with 1 mole of NaOH. Therefore, number of moles of HX = 0.00285 moles.
Molar mass = mass ÷ number of moles
= 0.281 ÷ 0.00285
= 98.6 g/mol.
Answer:
Explanation:
Chromatography is a technique for the separation of a mixture by passing it in solution or suspension through a medium in which the components move at different rates.Chromatography is also used to help catch criminals.Spoilage detection. Chromatography can be used in flavor studies and to detect spoilage in foods. Used in additive detection and used in determining nutritional quality.
Answer:
-372000 J or -372 KJ
Explanation:
We have the electrochemical reaction as;
Mg(s) + Fe^2+(aq)→ Mg^2+(aq) + Fe(s)
We must first calculate the E∘cell from;
E∘cathode - E∘anode
E∘cathode = -0.44 V
E∘anode = -2.37 V
Hence;
E∘cell = -0.44 V -(-2.37 V)
E∘cell = 1.93 V
n= 2 since two electrons were transferred
F=96,500C/(mol e−)
ΔG∘=−nFE∘
ΔG∘= -( 2 * 96,500 * 1.93)
ΔG∘= -372000 J or -372 KJ
Answer:
0.041 L = 41.3 mL
Explanation:
This problem we will solve by considering the stoichiometry of the reaction and the definition of molarity.
Number of moles in .800 L solution:
0.800 L x 0.0240 M = 0.800 L x .0240 mol/L = 0.0192 mol Fe³⁺
to form the precipitate Fe(OH)₃ we will need 3 times .0192
mol NaOH required = 0.057
given the concentration of 1.38 mol M NaOH we can calculate how many milliliters of NaOH will contain 0.057 mol:
1.L/1.38 mol NaOH x 0.057 mol NaOH = 0.041 L
0.041 L x 1000 mL/1L = 41.3 mL
Because it’s outermost ( actually , it’s only )
shell is full. The next shell holds 8 but it’s case it’s 2