The temperature in the stratosphere gets warmer with altitude. True False

In a metal what is not given an assigned location and thus can drift

Allushta [10]

In a metal, "Electrons" is not given an assigned location and thus can drift

In short, Your Answer would be Option C

Hope this helps!

6 0

2 years ago

N₂O(g) + 3 H₂(g) N₂H4(1) + H₂O(1) AH = -317 kJ/mol

docker41 [41]

Answer:

A

Explanation:

Recall that ΔH is the sum of the heats of formation of the products minus the heat of formation of the reactants multiplied by their respective coefficients. That is:

$\displaystyle \Delta H^\circ_{rxn} = \sum \Delta H^\circ_{f} \left(\text{Products}\right) - \sum \Delta H^\circ_{f} \left(\text{Reactants}\right)$

Therefore, from the chemical equation, we have that:

$\displaystyle \begin{aligned} (-317\text{ kJ/mol}) = \left[\Delta H^\circ_f \text{ N$_2$H$_4$} + \Delta H^\circ_f \text{ H$_2$O} \right] -\left[3 \Delta H^\circ_f \text{ H$_2$}+\Delta H^\circ_f \text{ N$_2$O}\right] \end{aligned}$

Remember that the heat of formation of pure elements (e.g. H₂) are zero. Substitute in known values and solve for hydrazine:

$\displaystyle \begin{aligned} (-317\text{ kJ/mol}) & = \left[ \Delta H^\circ _f \text{ N$_2$H$_4$} + (-285.8\text{ kJ/mol})\right] -\left[ 3(0) + (82.1\text{ kJ/mol})\right] \\ \\ \Delta H^\circ _f \text{ N$_2$H$_4$} & = (-317 + 285.8 + 82.1)\text{ kJ/mol} \\ \\ & = 50.9\text{ kJ/mol} \end{aligned}$

In conclusion, our answer is A.

5 0

2 years ago

Vanillin (used to flavor vanilla ice cream and other foods) is the substance whose aroma the human nose detects in the smallest

balu736 [363]

Answer:

Cost to supply enough vanillin is $3.2\$$

Explanation:

Threshold limit of vanillin in air is $2.0\times 10^{-11}g$ per litre means there should be $2.0\times 10^{-11}g$ of vanillin in 1L of air to detect aroma of vanillin.

$1ft^{3}=28.32L$

So, $5.0\times 10^{7}ft^{3}=(5.0\times 10^{7}\times 28.32)L$

So amount of vanillin should be present to detect = $(2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32)g$

As cost of 50 g vanillin is $112\$$ therefore cost of $(2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32)g$ vanillin = $(2.0\times 10^{-11}\times 5.0\times 10^{7}\times 28.32\times 112)\$ = 3.2\$$

5 0

3 years ago

Fill in the blank. _______rain falls in areas that have air pollution.

Genrish500 [490]

Acid rain falls in areas that have air pollution. (Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide)

7 0

3 years ago

Classify the substances according to the strongest solute-solvent interaction that will occur between the given substances and w

-BARSIC- [3]

Explanation:

Ion-dipole interactions are defined as the interactions that occur when an ion interacts with the dipole of a molecule (polar molecule).

For example, $CuCl_{2}$ , $CuSO_{4}$ , $CaCl_{2}$ , NaCl etc are all the molecules that will show ion-dipole interactions.

Dipole-dipole interactions are defined as the interactions that occur when partial positive charge on an atom is attracted by partial negative charge on another atom.

When a polar molecules produces a dipole on a non-polar molecule through distribution of electrons then it is known as dipole-induced forces.

For example, $NH_{3}$ , $CH_{3}OH$ etc are the molecules which show dipole-dipole interactions.

5 0

2 years ago