NaOH volume added BEFORE the largest pH increase _______________ mL _______________ mL NaOH volume added AFTER the largest pH in
crease _______________ mL _______________ mL Volume of NaOH needed to reach the equivalence point (calculated) _______________ mL _______________ mL Moles of NaOH added _______________ mol _______________ mol Concentration of unknown acid _______________ M _______________ M Average concentration of unknown acid and % error Avg [HA] = ________________ M __________ %
<span>The question says,'salt is the product formed by a reaction in which .............atoms of an acid are replaced by the atoms of a metal. The correct answer is hydrogen atoms. Salts are formed as a result of the hydrogen ions in the acid been replaced by metal ions or other positive ions in the base.</span>
Taking into account the definition of calorimetry, 0.0185 moles of water are required.
<h3>Calorimetry</h3>
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is defined as the amount of heat that a body absorbs or releases without any changes in its physical state (phase change).
So, the equation that allows to calculate heat exchanges is:
Q = c× m× ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
<h3>Mass of water required</h3>
In this case, you know:
Heat= 92.048 kJ
Mass of water = ?
Initial temperature of water= 34 ºC
Final temperature of water= 100 ºC
Specific heat of water = 4.186
Replacing in the expression to calculate heat exchanges:
92.048 kJ = 4.186 × m× (100 °C -34 °C)
92.048 kJ = 4.186 × m× 66 °C
m= 92.048 kJ ÷ (4.186 × 66 °C)
<u><em>m= 0.333 grams</em></u>
<h3>Moles of water required</h3>
Being the molar mass of water 18 , that is, the amount of mass that a substance contains in one mole, the moles of water required can be calculated as:
This question is incomplete but generally it seem to test the knowledge of accuracy. Accuracy is the closeness of a measured value to the specific or actual value of the substance being measured. Hence, the smaller the entire scale that can contain all the substance being measured, the higher the possibility of accuracy to be achieved. For example, a pen of 10.4 cm in length can be better/accurately measured (length) with a 30 cm meter rule than a 1 m meter rule.
From the question, the 50 mL beaker will provide a "more accurate" measurement of the volume of the bromine than the 100 mL beaker if the 50 mL beaker can contain all the sample of bromine water provided.