Answer:
The correct options are:
1) Pure chemical substance
2) Element.
Explanation:
each of the term is explained below:
1) <u>Mixture: </u> Since tungsten is an element in periodic table thus it is not a mixture.
2) False by definition of mixture.
3) false by definition of mixture.
4) <u>Solution:</u> Tungsten in a filament is in solid form hence solution is incorrect.
5) Since it is given in the question itself that the sample is pure hence option 'E' is correct as chemical substance is a pure substance that has a homogeneous composition and the sample in the question is given as pure.
6) <u>Compound:</u> By definition of compound it is formed by mixing 2 or more elements but since tungsten is an element that occurs independently in nature hence it is not a compound.
7) Tungsten is a element in the periodic table with atomic number 74.
In order to determine whether a bond is ionic or covalent, you need to know whether or not it is completely composed of nonmetal atoms or both metal and nonmetal ions.
Barium is a metal and Oxygen is a nonmetal, therefore there is no possible way they could bond unless they were attracted to opposite charges. Specifically, only if Barium becomes a cation and Oxygen becomes an anion then could they bond.
Now cation and anion both have the word "ion" in them, so therefore it must be an ionic bond.
Now we need to know the definition of a bond. A bond is formed when two elements are joined together by sharing their valence electrons.
Therefore, your answer should be:
Ionic, because valence electrons are shared.
Yes all living things are mad up of two or more cells
<span>The balloons volume as it
rises increases because at higher altitude external pressure is lower, so the
air molecules inside the balloons tends to expand more to attain mechanical
equilibrium, where the external pressure and internal pressure are equal. Unlike
when the balloon is on the ground, external pressure is great so the gas
molecule cannot push the walls of the balloon so it is like underinflated.</span>
There is enough wind power in the U.S. to drive the entire country, but aesthetic considerations cause some people to oppose its use.
