Help me with these questions please!!

Explanation:

Q 1;

Given data:

Mass of Na₂CO₃ produced = ?

Mass of sodium oxide = 50.0 g

Solution:

Chemical equation:

2Na₂O + CO    →     Na₂CO₃ + 2Na

Number of moles of sodium oxide:

Number of moles = mass/ molar mass

Number of moles = 50 g/ 62 g/mol

Number of moles = 0.806 mol

Now we will compare the moles of sodium oxide with sodium carbonate.

                              Na₂O          :               Na₂CO₃

                                 2              :                   1

                             0.806            :              1/2×0.81 = 0.403

Mass of sodium carbonate:

Mass = number of moles × molar mass

Mass = 0.403 mol × 106 g/mol

Mass = 42.7 g

Q 2;

Given data:

Moles of Al₂(SO₄)₃ produced = ?

Mass of Al = 35 g

Solution:

Chemical equation:

2Al + 3H₂SO₄    →     Al₂(SO₄)₃ + 3H₂

Number of moles of Aluminium:

Number of moles = mass/ molar mass

Number of moles = 35 g/ 27 g/mol

Number of moles = 1.3 mol

Now we will compare the moles of sodium oxide with sodium carbonate.

                              Al               :            Al₂(SO₄)₃

                               2               :                   1

                             1.3               :              1/2×1.3 = 0.65

So from 35 gram of Al 0.65 moles of Al₂(SO₄)₃ are produced in the presence of excess sulfuric acid.

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

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).