If 4.74 g of propane is allowed to completely combust, calculate the mass of carbon dioxide formed at the end. Remember the units

14.2g

Explanation:

The reaction expression is given as:

        C₃H₈  +  5O₂ → 3CO₂ + 4H₂O

Given mass of propane combusted;

   4.74g

Unknown:

Mass of carbon dioxide produced  = ?

Solution:

To solve this problem, we find the number of moles of the given propane;

   Number of moles  =  

Molar mass of C₃H₈ = 3(12) + 8(1) = 44g/mol

   Number of moles  =  = 0.11mol

From the balanced reaction equation:

          1 mole of C₃H₈ will produce  3 moles of CO₂

          0.11mole of C₃H₈ will produce 3 x 0.11  = 0.33mole of  CO₂

Mass of  CO₂ = number of moles x molar mass

    Molar mass of  CO₂ = 12 + 2(16) = 44g/mol

Mass of  CO₂ = 0.33 x 44  = 14.2g

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).