Answer:
Molar mass of Na2HPO4=141.96, of Na2HPO4. 12H2O = 358.14: so to get the same 0.4 M: 28.65/358.14*141.96 g, add water until you reach 200ml , dissolve all solid and then filter to make sterile.
Explanation:
Answer: The density of the liquid is 
Explanation:
Density is defined as the mass contained per unit volume.
Given : Mass of the unknown liquid = 938 grams
Volume of the unknown liquid = 
Putting in the values we get:
Thus the density of the liquid is and the liquid is dimethyl sulfoxide.
Answer:
a. 2954g of FeS
b. 1143g of FeS
Explanation:
Based on the reaction:
8 Fe + S₈ → 8 FeS
<em>8 moles of Fe reacts with 1 mole of S₈ to produce 8 moles of FeS</em>
<em />
a. 4.2mol sulfur produce:
4.2mol S₈ × ( 8 mol FeS / 1 mol S₈) = <em>33.6mol FeS</em>. As molar mass of FeS is 87.92g/mol, mass is:
33.6mol FeS × ( 87.92g / 1 mol FeS) = <em>2954g of FeS</em>
<em />
b. 13mol Fe produce:
13mol Fe × ( 8 mol FeS / 8 mol Fe) = <em>13mol FeS</em>. In mass:
13 mol FeS × ( 87.92g / 1 mol FeS) = <em>1143g of FeS</em>
Answer:
Solid KOH will corrode the skin but a solution of KOH in triethyleneglycol will not.
The temperature is monitored with an external thermometer also because the sand looses some heat to energy exchange with the surrounding.
Explanation:
KOH is a deliquescent solid which is very corrosive upon contact with skin. Its solution in an organic liquid is not corrosive.
Secondly, when exposed to the surrounding, heat is lost according to the laws of thermodynamics.
