A scientist was in the field when he saw a mineral sample. He wanted to determine the relative hardness of the mineral, so he conducted scratch tests. He summarized his results in a table. What conclusion can you make about the hardness of the mineral?

You exhale co2 which is produced during cellular respiration.  co2 combines with the water in your blood's plasma to make up one half of the body's most important buffer pair, carbonic acid.  the more physical activity you engage in, the more co2 your body is producing.  you can see this by putting some of the cabbage indicator in a glass and then blowing bubbles into it through a straw.  can you see a change in the color of the indicator?

The molecular weight of carbon dioxide, co2, is 44.00 amu, and the molecular weight of nitrous dioxide, no2, is 46.01 amu, so no2 diffuses co2

What is the significant digit in 23.45