For which applications would you choose a liquid over a gas or solid?

Answer:

The accurate answer is 596.5 kJ.

Explanation:

The question specifies that the mass of ethanol, C2H5OH, is 20 grams.

The molar mass of ethanol is 46 g/mol.

To find the moles of ethanol, we use the formula:

n = mass / molar mass

= 20/46 = 0.435 moles

According to the question, the standard heat of combustion for ethanol is 1372 kJ/mol. Hence, one mole releases 1372 kilojoules during combustion.

The energy produced from burning 20 grams of ethanol completely is 0.435 * 1372 = 596.5 kJ.

The formula for Molarity is given by:

                                  M = moles / V
To isolate V,
                              V = moles / M ------------------(1)
Moles can also be calculated as:
                                  moles = mass / M.mass -------------(2)
Substituting the value of moles from equation 2 into equation 1 yields:
                                  V = (mass / M.mass) / M
Plugging in the numbers gives:
                                  V = (45 g / 164 g/mol) / 1.3 mol/dm³

                                       V = 0.21 dm³.

Although multiple values are given, our focus is on HCl.

<span>We have 215 mL (0.215 L) of 0.300 M HCl fully consumed in the reaction. It's important to recall that the number of moles is found by multiplying volume by molarity:</span>

 

moles = 0.215 L × 0.300 M

<span>moles = 0.0645 moles of HCl</span>

Answer:

Explanation:

Greetings,

According to the provided chemical equation, the production of 31.2 mL of hydrogen allows one to calculate its moles using the ideal gas equation as detailed below:

Since the ratio of hydrogen to magnesium is 1:1, its milligrams are derived through the following proportional factor calculation:

Regards.

The resulting temperature, following the change in volume and pressure, is -27.26°C. To find this temperature, we apply the combined gas law equation—a formulation where initial and final pressures, volumes, and temperatures are compared. Given the initial conditions and transformations, when we input the stipulated values, we reach the conclusion that the resultant temperature is -27.26°C.