Answer:
Infectious diseases are commonly transmitted through direct person-to-person contact.
The main four pathogens are virus, bacteria, protists and fungi.
Bacteria, fungi and protists can reproduce wherever the conditions are warm, with plenty of moisture, nutrients, and space. Viruses can only reproduce by invading living cells.
Answer: released to; absorbed from
- In an exothermic reaction, energy is released to the surroundings.
- In an endothermic reaction, energy is absorbed from the surroundings.
Explanation:
An exothermic reaction is a chemical reaction that occurs spontaneously and brings about the release of energy to the surroundings. Hence, the reacting vessel feels hot as the reaction proceeds.
An endothermic reaction, on the other hand, does not occur spontaneously and proceed only when energy is absorbed from the surroundings. Hence, the reacting vessel feels cold as the reaction proceeds.
The molecular formula of the compound that has a percent composition of 38.7% carbon, 9.76% hydrogen, 51.5% oxygen is C2H6O2.
<h3>How to calculate molecular formula?</h3>
The molecular formula can be calculated from the empirical formula. The empirical formula of the compound is calculated as follows:
- C = 38.7% = 38.7g
- H = 9.76% = 9.76g
- O = 51.5% = 51.5g
Next, we convert the mass to moles by dividing by their atomic mass:
- C = 38.7 ÷ 12 = 3.23mol
- H = 9.76 ÷ 1 = 9.76mol
- O = 51.5÷ 16 = 3.22mol
Next, we divide by the smallest (3.22)
Hence, the empirical formula of the compound is CH3O
If the molar mass of the compound is 62g/mol;
(CH3O)n = 62
31n = 62
n = 2
(CH3O)2 = C2H6O2
Therefore, the molecular formula of the compound that has a percent composition of 38.7% carbon, 9.76% hydrogen, 51.5% oxygen is C2H6O2.
Learn more about molecular formula at: brainly.com/question/14425592
Answer:

Explanation:
Percent yield is the ratio of the amount actually produced to how much could theoretically be produced. It is found using this formula:

For this reaction, the theoretical or expected yield is 325.0 grams. The actual yield is 123.8 grams.

Divide.


Round to the nearest hundredth. The 9 in the hundredth place tells us to round the 0 to a 1 .

The percent yield is about <u>38.1%</u>