Answer:
air is not a mixture because of scientists freezing it and finding different liquids, it is a mixture because the compounds that make up air e.g. oxygen (o2), Carbon dioxide (co2) and the most important Nitrogen which is an element and makes up 78.09% of air are not chemically bound in the way that compounds are
Explanation:
Answer:
78.85
Explanation:
To <u>calculate the average atomic mass of the isotopes </u>we use the <em>given masses and abundances</em>, as follows:
- Mass of Isotope 1 * Abundance of Isotope 1 + Mass of Isotope 2 * Abundance of Isotope 2 + ....
In other words:
- 78 amu * 75/100 + 81 amu * 15/100 + 82 amu * 10/100 = 78.85
So the answer is 78.85.
Answer:
See the answer below
Explanation:
There are several scientists that contributed to the understanding of the cell. Some of them and their contributions are as follows:
Anton van Leeuwenhoek: He invented the first primitive microscope and was able to view some unicellular microscopic cells such as protozoans and bacteria. He disproved the theory of spontaneous generation by his discoveries.
Robert Hooke (1665): He improved further on the microscope invented by Leeuwenhoek and was able to view compartment-like rooms when tissues of cork were sectioned. He tagged the compartment as 'cell'.
Schleiden (1804–1881): Using an improved microscope, he was able to extensively study plant tissues and borrowed the word coined by Hooke (cell) to describe the component of the plant tissues.
Theodor Schwann (1810–1882): He studied animal tissues and made a similar observation as Schleiden.
Through their various studies, Schleiden, Schwann, and another scientist, Rudolf Virchow later developed what is nowadays known as the cell theory
Given the choices;
a) Bourdon gauge flowmeter
b) Hudson gauge flow meter
c) Constant flow selector
d) pressure compensated flowmeter.
The one that can only be used upright is the pressure-compensated flowmeter. Compensated flowmeters work with a variable orifice and fixed pressure. They read back pressure, and take into account resistance changes down stream from the needle valve. If pressure exceeds 50psig downstream, flow ceases.
