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The reaction that the graph represents is
A. Exothermic because Hrxn=-167 kJTo calculate Hrxn we apply the following equation:

Looking at the graph, and at the result of the calculations, we can see that the enthalpy of the products is
lower than the enthalpy of the reagents, because the sign is negative. That means that the reaction
releases energy in the form of heat and that the reaction is
exothermic.
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Fungi cannot make their food from sunlight, water and carbon dioxide as plants do, in the process known as photosynthesis
Answer:

Explanation:
<u>1. Convert Grams to Moles</u>
Use the molar mass (found on the Periodic Table) to convert from grams to moles.
Use this value as a ratio.

Multiply by the given number of grams.

Flip the ratio so the grams of boron cancel out.



<u>2. Convert Moles to Atoms</u>
We use Avogadro's Number, 6.02*10²³: the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of boron.

Multiply by the number of moles we calculated.

The moles of boron cancel.


The original value of grams has 4 significant figures, so our answer should have the same. For the number we calculated, that is the thousandth place.

The 6 tells us to round the 2 to a 3.

25.00 grams of boron is equal to 1.393*10²⁴ atoms.
Answer:
The total pressure will be 1, 021 atm
Explanation:
We apply Dalton's law, where for a gas mixture the total pressure is the sum of the partial pressures of each gas that makes up that mixture. The unit of pressure is converted into atm:
760mmHg----1 atm
542mmHg----x=(542mmHgx 1 atm)/760mmHg=0,713 atm
234mmHg----x=(234mmHgx 1 atm)/760mmHg=0,308 atm
Pt=P Ne + P At= 0,713 atm + 0,308 atm= <em>1, 021 atm</em>