Answer:
Some common compounds in our daily lives:
Water, H2O. We need this for survival, because it serves a lot of functions in our body, such as being a medium for chemical reactions in our cells.
Carbon Dioxide, CO2. It is one of the components of air, our body also produces CO2 during respiration.
Sodium chloride, NaCl. Table salt is mostly made of sodium chloride. It is also found dissolved in sea water.
Methane, C2H4. This is a common fuel for generating electricity. It can also be found (small amounts) in air.
Nitrogen Dioxide, NO2. It can also be found in air, and it is one of the common air pollutants brought by burning of fossil fuels.
The boiling point (or condensation point) of a substance is defined as the temperature at which the vapor pressure of the liquid is exactly equal to the external pressure. Above the boiling point, the substance exists as a gas and below, it exists predominately as a liquid.
hydrogen is the lightest element in the periodic table
Answer:
The correct answer is - sulfur.
Explanation:
In the periodic table, there are 18 groups and 7 rows or periods arranged according to their atomic number or electronic configuration. In the question, it is mentioned that the desired element atomic mass is less than the atomic mass of the selenium which is 78.96, and more than oxygen which is 15.99 with 6 electron valence and present in the third row.
As it has 6 valency of electron it must be in the 16 group of the table that comprises the 6 valency and as it is located in the 3rd row it must be sulfur that also has an atomic mass between selenium and oxygen.
i think its theory but im not to sure
