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4 years ago

It

Chemistry

1 answer:

ivann1987 [24]4 years ago

5 0

Answer:

His mistake was that he also gave the plants in the music room some fertilizer

Explanation:

When carrying out a reliable experiment, the only variable should be the question being tested. The question here is whether playing music for plants helps them grow faster. Therefore, all the plants should be grown in exactly the same conditions apart from the presence or absence of music.

However, Jo also added fertilizer to the plants in the room where music was playing. Therefore, we don't know whether the fertilizer or the music caused the plants to grow faster.

Instead, Jo should have not given fertilizer to any of the plants, or given fertilizer to all the plants.

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What can cells create

liraira [26]

Cells are the basic structures of all living organisms. Cells provide structure for the body, take in nutrients from food and carry out important functions. Cells group together to form tissues, which in turn group together to form organs, such as the heart and brain.

3 0

3 years ago

What is a possible quantum number set for an electron in the 3s orbital of a magnesium atom

Alik [6]

n = 3
l = 0
$m_l$ = 0

$m_s$ = 1/2 or -1/2

<h3>Explanation</h3>

There are four quantum numbers in an electron that orbits the atom.

n, the principal quantum number.
l, the angular quantum number.
$m_l$ , the magnetic quantum number.
$m_s$ , the spin quantum number.

n is a positive integer. The value of n indicates the main shell of the electron. The electron in question is in the 3s orbital. As a result, n = 3.

l is a non-negative integer. The value of l indicates the type of subshell ("orbital") of the electron. The types of subshells possible depends on the main shell. For example, both s and p orbitals exist in the second main shell. However, only the s orbital exists in the first main shell. The value of l ranges from 0 to n - 1.

l = 0 indicates an s orbital.
l = 1 indicates a p orbital.
l = 2 indicates a d orbital.
l = 3 indicates an f orbital.

The electron in question is in an s orbital. As a result, l = 0.

$m_l$ is an integer. The value of $m_l$ indicates the position of the electron within the subshell. The range of $m_l$ depends on the value of l. $m_l$ ranges from -l to l (that's -l, ..., -1, 0, 1, ... l). Accordingly, there are 2 l + 1 orbitals in a l subshell. l = 0 for this 3s electron. There's only one orbital in the 3s subshell. The only $m_l$ value possible for this electron is 0.

The value of $m_s$ is either - 1/2 or 1/2. It indicates the position of an electron within a single orbital. The value of $m_s$ does not depend on that of n, l, or $m_l$ . However, by the Pauli Exclusion Principle, at least one of the four numbers must differ for two electrons in the same atom. In case all three of n, l, and $m_l$ are the same, the two electrons must differ in $m_s$ . However, this question asks only for the number of one single electron. Thus, giving either - 1/2 or 1/2 shall work.

<h3>Reference</h3>

Vitz et. al, "5.8 Quantum Numbers (Electronic)", ChemPRIME (Moore et al.), Chemistry Libretexts. 27 Oct 2017.

7 0

4 years ago

You wish to make a buffer with pH 7.0. You combine 0.060 grams of acetic acid and 14.59 grams of sodium acetate and add water to

aleksandr82 [10.1K]

Answer:

The pH of the buffer is 7.0 and this pH is not useful to pH 7.0

Explanation:

The pH of a buffer is obtained by using H-H equation:

pH = pKa + log [A⁻] / [HA]

Where pH is the pH of the buffer

The pKa of acetic acid is 4.74.

[A⁻] could be taken as moles of sodium acetate (14.59g * (1mol / 82g) = 0.1779 moles

[HA] are the moles of acetic acid (0.060g * (1mol / 60g) = 0.001moles

Replacing:

pH = 4.74 + log [0.1779mol] / [0.001mol]

pH = 6.99 ≈ 7.0

The pH of the buffer is 7.0

But the buffer is not useful to pH = 7.0 because a buffer works between pKa±1 (For acetic acid: 3.74 - 5.74). As pH 7.0 is out of this interval,

this pH is not useful to pH 7.0

7 0

3 years ago

1. Criminal profiling assigns crimes as one of two kinds. If a criminal profiler was looking at a case that involved a sophistic

amm1812

Answer:

So, for 1 I am most certain it has to be Organized so C. And for 2 that would be true if my brain isn't failing me- I hope this helps!

Explanation:

4 0

3 years ago

Read 2 more answers

10. Which substance does not take the shape of its container?

luda_lava [24]

Answer:

B. Air

Explanation:

5 0

3 years ago