Answer:
A
Explanation:
The mass number (represented by the letter A) is defined as the total number of protons and neutrons in an atom. Consider the table below, which shows data from the first six elements of the periodic table. Consider the element helium. Its atomic number is 2, so it has two protons in its nucleus.
Hey there!
The molar mass of nitrogen is 14.007.
Convert grams to moles:
21.2 ÷ 14.007 = 1.51
The sample containing 21.2g of nitrogen contains 1.51 moles of nitrogen.
Hope this helps!
Because of pollution from factories and other activities that release harmful gases into the air
Answer:
The balloon becomes inflated
Explanation:
The equation of the reaction between baking soda (sodium bicarbonate) and vinegar(ethanoic acid) is shown below;
NaHCO3 + HC2CH3O2 ------> NaC2H3O2 + H2O + CO2
The gas (CO2) evolved in the process leads to the inflation of the balloon dropped on the bottle in which the reaction is taking pace.
This observation provides evidence that a gas was really evolved in the reaction.
