A. The atmosphere
All the other examples are either elements or compounds, not mixtures. A mixture is a combination of elements that are not chemically or irreversibly conjoined so the atmosphere, made up of a variety of gases, would be a mixture.
Answer:
3270m
Explanation:
1 minute= 109m
so
30 minutes= 109 × 30 = 3270m
(whatever you do on one side you have to do to the other)
hope this helps :)
Answer:
True
Explanation:
Resonance is a concept that was introduced when it was not possible to represent a compound with a single Lewis structure. Lewis formulas represent localized electrons, either shared by two atoms in a covalent bond or as non-shared electrons belonging to a given atom. Certain organic compounds, especially those containing multiple bonds can be described by more than one Lewis structure. In these cases, the true Lewis structure has an electronic distribution that is a "hybrid" of all possible Lewis structures of that molecule. Each of Lewis's structures is known as resonance or canonical forms and they are related to each other by a double-headed arrow, where all possible positions of electrons in that molecule are represented.
This type of compound has multiple bonds (double or triple) where electrons are not fixed, but move quickly between atoms, "resonating" between the different Lewis structures. For this reason, when a resonance hybrid has a negative charge, this charge moves between the different resonant structures.
Many times, an intermediate Lewis structure is drawn, with dotted lines, simulating approaching the real structure of the compound, and where this phenomenon of electron and charge mobility can be observed. For example, as we can observe in the ozone resonance image.
Answer:

Explanation:
Hello!
In this case, considering that the mass of hydrazine is missing, we can assume it is 130.0 g (a problem found on ethernet). In such a way, since we need a mass-mole-atoms relationship by which we can compute moles of hydrazine given its molar mass (32.06 g/mol), then the moles of hydrogen considering one mole of hydrazine has four moles of hydrogen and one mole of hydrogen has 6.022x10²³ atoms (Avogadro's number); therefore, we proceed as shown below:

Notice 130.0 g has four significant figures, therefore the result is displayed with four as well.
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Answer:
in illustration 1
the mother told her son not to play with the boy having cough because it is a transferable disease which could cause him also to get sick and would get cough.
while in
illustration 2
the mother let the boy play with the boy having asthma because it is not a transferable disease which wold not affect him or any one else.
Explanation:
this is the reason