The independent variable is a variable that is being manipulated or controlled. This is to see how it affects, changes and yields the outcome of the particular stimuli.
The dry ice experiment has an IV of temperature and a DV of melting time.
Molar mass :
NaBr = 103 g/mol
Pb(NO3)2 = 331.20 g/mol
<span><span /><span>Balanced chemical equation :
</span></span>2 NaBr + 1 Pb(NO3)2 = 2 NaNO3 + 1 PbBr<span>2
</span><span>
2*103 g NaBr ------------> 1 * 331.20 g Pb(NO3)2
g NaBr -------------------> 311 g Pb(NO3)2
331.20 g = 2*103*311
331.20 g = 64066
mass ( NaBr ) = 64066 / 331.20
mass ( naBr) = 193,43 g of NaBr
hope this helps!.
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*A & B*
Answers A & B are not possible, as Hydrogen “bonds” are intermolecular forces and do not actually involve transfer or sharing of electrons.
*C & D*
Viscosity and surface tension are not the answer as they are not specific enough to the question.
*E*
Polarity of water molecules is the correct answer, as water molecules are highly polar. The partial positive of the Hydrogen on one water molecule is highly attracted to the partial negative of the Oxygen (due to its lone pairs) on another water molecule.
Answer:
Temporary in nature.
No new substance is formed.
Explanation:
Temporary in nature: Does not affect the internal structure of a substance, only the molecules are rearranged.
No new substance is formed: Most of the physical changes are reversible. We can obtain the substance back even after the change.
hope this helps
have an awesome day -TJ
Explanation:
The rest of the energy is passed on as food to the next level of the food chain. The figure at the left shows energy flow in a simple food chain. Notice that at each level of the food chain, about 90% of the energy is lost in the form of heat.
