1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
True [87]
3 years ago
6

In the early twentieth century, what was Alexander Fleming’s hypothesis concerning the relationship between a yellow-green mold

and certain strains of bacteria?
a. He thought the bacteria had released a chemical that caused the mold to grow. b.He thought the bacteria fed on the mold, causing it to shrink and disappear.
c. He thought the mold had released a chemical that prevented the bacteria’s growth.
Chemistry
1 answer:
SpyIntel [72]3 years ago
4 0

Answer:

The correct answer is the option c)He thought the mold had released a chemical that prevented the bacteria’s growth.

Explanation:

In the 1920s, Alexander Fleming was working in his laboratory at St. Mary's Hospital in London when, almost by accident, he discovered a naturally growing substance that could attack certain bacteria. In one of his experiments, Fleming observed that colonies of a bacterium had been depleted or removed by a mold that grew on the same Petri dish. He observed that the bacteria furthest from the fungus had grown to produce large-sized colonies, while the colonies closest to the fungus were tiny. He determined that mold made a substance that could dissolve bacteria. The fungus was penicilium chrysogenum and thus Fleming called this substance penicillin, by the name of the mold that produces it. Thus, after several years of experiments in 1930, Howard Florey and Ernest Chain developed at Oxford University the procedures to produce pure penicillin from the fungus that Fleming isolated. Thus penicillin could be concentrated by Florey and Chain, and in 1945 they shared with Fleming the Nobel Prize in Medicine.

Then, <u><em>the correct answer is the option c)He thought the mold had released a chemical that prevented the bacteria’s growth.</em></u>

You might be interested in
A package of chocolate instant pudding contains 2640 mg of sodium. how many grams of sodium are in the pudding?
alexgriva [62]

Answer:

2.640

Explanation:

Rounding to the nearest whole number would be 3 if that is needed.

4 0
2 years ago
How many moles are represented by 3.01 x10^24 oxygen atoms?
asambeis [7]
<h3>Answer:</h3>

5.00 mol O₂

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

  • Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.<u> </u>

<u>Stoichiometry</u>

  • Using Dimensional Analysis
<h3>Explanation:</h3>

<u>Step 1: Define</u>

3.01 × 10²⁴ atoms O₂

<u>Step 2: Identify Conversions</u>

Avogadro's Number

<u>Step 3: Convert</u>

  1. Set up:                              \displaystyle 3.01 \cdot 10^{24} \ atoms \ O_2(\frac{1 \ mol \ O_2}{6.022 \cdot 10^{23} \ atoms \ O_2})
  2. Multiply/Divide:                \displaystyle 4.99834 \ mol \ O_2

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 3 sig figs.</em>

4.99834 mol O₂ ≈ 5.00 mol O₂

4 0
3 years ago
What type of energy does a cup sitting on a table have? Why?
Sedbober [7]

Answer:

POTENTIAL ENERGY

A cup sitting on a table possesses potential energy

Explanation:

Answer Expert Verified

5 0
3 years ago
QUESTION 10
iris [78.8K]

Answer:

B

Explanation:

Phosphofructokinase-1

6 0
2 years ago
The molar heat of fusion of gold is 12.550 kJ mol–1. At its melting point, how much mass of melted gold must solidify to release
KATRIN_1 [288]

The mass of melted gold to release the energy would be  3, 688. 8 Kg

<h3>How to determine the mass</h3>

The formula for quantity of energy is given thus;

Q = n × HF

Where n represents number of moles

HF  represents  heat of fusion

To find the number of moles, we have

235.0 = n × 12.550

number of moles = \frac{235}{12. 550} = 18. 725 moles

Note that molar mass of Gold is 197g/ mol

Let's note that;

Number of moles = mass/ molar mass

Mass = number of moles × molar mass

Mass = 18. 725 × 197

Mass = 3, 688. 8 Kg

Thus, the mass of melted gold to release the energy would be  3, 688. 8 Kg

Learn more about molar heat of fusion here:

brainly.com/question/15634085

#SPJ1

8 0
2 years ago
Other questions:
  • Which of the following is an nonmetal?<br> A. He<br> B. Re<br> C. Cu<br> D.Hg
    7·1 answer
  • Which activity would be an appropriate first step when designing an experiment?
    11·2 answers
  • I WILL GIVE BRAINLIEST!
    15·2 answers
  • Bohr models notes <br> The number of periods shows you the number of _______
    14·1 answer
  • What is an isotope and how does their abundance in nature differ from element to element
    10·1 answer
  • The gases carbon dioxide, oxygen, and argon are mixed in a container. All gases have the same partial pressure, and the total pr
    10·1 answer
  • What is the difference between a Stalagmite and a stalactite?​
    13·1 answer
  • Which represents the correct order in which oxygen enters the body?
    6·1 answer
  • I need answers to all of them
    11·1 answer
  • ZnCo3 how do I decomposition this
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!