Answer:
4.74 × 10³ mg
Explanation:
Given data
- Health risk limit for chloroform in groundwater: 60.0 g/L
- Volume of the sample of groundwater: 79.0 mL = 79.0 × 10⁻³ L
The maximum mass of chloroform that there could be in the sample of groundwater to meet the standards are:
79.0 × 10⁻³ L × 60.0 g/L = 4.74 g
1 gram is equal to 10³ milligrams. Then,
4.74 g × (10³ mg/1 g) = 4.74 × 10³ mg
C. Solid
Although molarity is commonly used to express concentrations for reactions in solution or for titrations, it does have one drawback—molarity is the number of moles of solute divided by the volume of the solution, and the volume of a solution depends on its density, which is a function of temperature.
The mass of sodium hydrogen carbonate : 10.5 g
<h3>Further explanation</h3>
Given
1.5 dm' of CO₂
1 mol gas= 24 L at RTP(25 °C, 1 atm)
Required
the mass of sodium hydrogen carbonate
Solution
Decomposition reaction of Sodium hydrogen carbonate :
2 NaHCO₃ (s) ⇒ Na₂
CO₃ (s) + H₂
O(g) + CO₂ (g)
mol CO₂ :
From the equation, mol ratio of NaHCO₃ : CO₂ (g) = 2 : 1, so mol NaHCO₃ :
Mass NaHCO₃(MW=23+1+12+3.16=84 g/mol) :
Very bad written question
C, then, D, A
A reaction that is spontaneous means that it can produce products without the supply of energy. The total energy from the reactants reached the activation energy that allow the reaction proceed. An example of this is the decay of a diamond into graphite occuring readily.
