What are the SI units of frequency?

Pepsi [2]

Answer:

The theory for the origin and evolution of the universe is the Big Bang model, which states that the universe began as an incredibly hot, dense point roughly 13.7 billion years ago.

7 0

3 years ago

Assume you are working for a chemical company and are responsible for growing a yeast culture that produces ethanol. The yeasts

romanna [79]

Answer:

Respiration might occur in the presence and absence of oxygen known as the aerobic respiration and anaerobic respiration. The ATP molecules are produced more in number in aerobic respiration.

The yeast has the ability to undergo the process of anaerobic respiration and its end product are alcohol, carbon dioxide and 2 moles of ATP. The yeast is grown on maltose medium but unable to produce alcohol because of the presence of oxygen in the medium. The oxygen might acts as poison or inhibit the process of anaerobic respiration.

6 0

3 years ago

Doctors have fought infections with penicillin for over 50 years. Recently, penicillin has not worked as well as before. Which o

Lilit [14]

C. "A" mentions that the drug killed all of the bacteria that are resistant to the drug, and that doesn't make any sense. "B" claims that all bacteria are resistant to the drug. This is not true. "D" mentions that bacteria eat the drug, which doesn't happen.

5 0

3 years ago

The metal content of iron in ores can be determined by a redox procedure in which the sample is first oxidized with Br2 to conve

coldgirl [10]

Answer:

80.27%

Explanation:

Let's consider the following balanced equation.

2 Fe³⁺(aq) + Sn²⁺(aq) ⇒ 2Fe²⁺(aq) + Sn⁴⁺(aq)

First, we have to calculate the moles of Sn²⁺ that react.

$\frac{0.1015molSn^{2+} }{1L} .13.28 \times 10^{-3} L=1.348\times 10^{-3}molSn^{2+}$

We also know the following relations:

According to the balanced equation, 1 mole of Sn²⁺ reacts with 2 moles of Fe³⁺.
1 mole of Fe³⁺ is oxidized from 1 mole of Fe.
The molar mass of Fe is 55.84 g/mol.

Then, for 1.348 × 10⁻3 moles of Sn²⁺:

$1.348\times 10^{-3}molSn^{2+}.\frac{2molFe^{3+} }{1molSn^{2+} } .\frac{1molFe}{1molFe^{3+} } .\frac{55.84gFe}{1molFe} =0.1505gFe$

If there are 0.1505 g of Fe in a 0.1875 g sample, the mass percentage of Fe is:

$\frac{0.1505g}{0.1875g} \times 100 \% = 80.27\%$

5 0

4 years ago

Which is the Lewis structure for H3PO4?

Fed [463]

Answer:

The correct structure of phosphoric acid is A.

Explanation

P should form five covalent bonds. In this strcuture P form three single bond with 3-hydroxyl groups while one single bondformed with oxygen. As oxygen will form two bonds , it carry negative charge, while P should form five bond but here it is forming 4 bonds due to this P has positive charge but overall structure contain neutral charge due to cancellation of positive and negative charges. Beside this, there are 3 H, Four O and One P according to formula H3PO4.

5 0

4 years ago