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2 years ago

Which chemical do you think would best maintain the pH of the pool water?

Chemistry

2 answers:

Pepsi [2]2 years ago

7 0

The answer is Bleach.

Explanation:

Hey, I might not be the best in chemistry but I do know the answer to this question!

malfutka [58]2 years ago

6 0

Answer: Bleach

Explanation:

You might be interested in

9. The times of first sprinkler activation (in seconds) for a series of tests of fire-prevention sprinkler systems that use aque

Nezavi [6.7K]

This question is incomplete, the complete question is;

The times of first sprinkler activation (in seconds) for a series of tests of fire-prevention sprinkler systems that use aqueous film-forming foam is as follows; 27 41 22 27 23 35 30 33 24 27 28 22 24

( see " use of AFFF in sprinkler systems," Fire technology, 1975: 5)

The system has been designed so that the true average activation time is supposed to be at most 25 seconds.

Does the data indicate the design specifications have not been met?

Test the relevant hypothesis at significance level 0.05 using the P-value approach

Answer:

since p-value (0.042299) is lesser than the level of significance ( 0.05)

We Reject Null Hypothesis

Hence, There is no sufficient evidence that the true average activation time is at most 25 seconds

Explanation:

Given the data in the question;

lets consider Null and Alternative hypothesis;

Null hypothesis H₀ : There is sufficient evidence that the true average activation time is at most 25 seconds

Alternative hypothesis H₁ : There is no sufficient evidence that the true average activation time is at most 25 seconds

i.e

Null hypothesis H₀ : μ ≤ 25

Alternative hypothesis H₁ : μ > 25

level of significance σ = 0.05

first we determine the sample mean;

$x^{bar}$ = $\frac{1}{n}$ ∑ $x_{i}$

where n is sample size and ∑ $x_{i}$ is summation of all the sample;

= $\frac{1}{13}$ ( 27 + 41 + 22 + 27 + 23 + 35 + 30 + 33 + 24 + 27 + 28 + 22 + 24 )

= $\frac{1}{13}$ ( 363

sample mean $x^{bar}$ = 27.9231

next we find the standard deviation

s = √( $\frac{1}{n-1}$ ∑( $x_{i}-x^{bar}$ )²

x ( $x_{i}-x^{bar}$ ) ( $x_{i}-x^{bar}$ )²

27 -0.9231 0.8521

41 13.0769 171.0053

22 -5.9231 35.0831

27 -0.9231 0.8521

23 -4.9231 24.2369

35 7.0769 50.0825

30 2.0769 4.3135

33 5.0769 25.7749

24 -3.9231 15.3907

27 -0.9231 0.8521

28 0.0769 0.0059

22 -5.9231 35.0831

24 -3.9231 15.3907

sum 378.9229

so ∑( $x_{i}-x^{bar}$ )² = 378.9229

∴

s = √( $\frac{1}{13-1}$ ×378.9229 )

s = √31.5769

standard deviation s = 5.6193

now, the Test statistics

t = ( $x^{bar}$ - μ ) / $\frac{s}{\sqrt{n} }$

we substitute

t = ( 27.9231 - 25 ) / $\frac{5.6193}{\sqrt{13} }$

t = 2.9231 / 1.5585

t = 1.88

now degree of freedom df = n - 1 = 13 - 1 = 12

next we calculate p-value

p-value = 0.042299 ( using Execl's ( = TDIST(1.88,12,1)))

Here x=1.88, df=12, one tail

now we compare the p-value with the level of significance

since p-value (0.042299) is lesser than the level of significance ( 0.05)

We Reject Null Hypothesis

Hence, There is no sufficient evidence that the true average activation time is at most 25 seconds

3 0

3 years ago

7. Which of these is not matter?<br> a. a cloud<br> c. sunshine<br> b. your hair<br> d. the sun

PilotLPTM [1.2K]

Hair ????????????????!?????

3 0

2 years ago

How many moles of calcium are there in 5.74 x 1022 atoms of calcium?

igor_vitrenko [27]

Answer:

0.095 moles of Calcium is there in 5.74 x 1022 atoms of calcium.

Explanation:

As we know, 6.023*10^23 atoms of an element is equal to its atomic weight.

And, 6.023*10^23 atoms of an element is also equal to 1 mole of the element.

We have,

6.023*10^23 atoms of element calcium equals to 1 mole of Calcium
5.74*10^22 atoms of element calcium equals to

(1/(6.023*10^.23)) * 5.74*10^22 moles of calcium

Therefore,

5.74 x 1022 atoms of calcium= 0.095 moles of calcium.

6 0

3 years ago

True or False When one side of a molecule is electronegative (δ-) and the other side of the

lesya [120]

Answer:

True; When one side of a molecule is electronegative (δ-) and the other side of the

molecule is electropositive (δ+), it is said to have a dipole moment.

Explanation:

A dipole moment exists in a molecule as a result of differences in the electronegativity values between the atoms of the elements involved in the chemical bonding.

When a strogly electronegative atom such as oxygen or chlorine is chemically bonded to a less electronegative or an electropositive atom such as hydrogen, there is an uneven sharing of the electrons involved in the bonding. The more electronegative atoms tends to draw the shared electrons mostly to themselves. This induces a partially negative charge (δ-) on them while leaving the electropositive atoms with a partially positive charge (δ+).

Water is an example of a molecule having a dipole moment. The oxygen atoms are more electronegative than hydrogen and as such draw the shared electrons to themselves more, inducing a partial positive charge (δ+) on the hydrogen atoms while they themselves develop a partial negative charge (δ-).

8 0

2 years ago

Fe(s) + CuSO4(aq) ⇒ Cu(s) + FeSO4(aq)

Alexxandr [17]

Answer:

The answer to your question is CuSO₄

Explanation:

To answer your question just remember the following information

- A chemical reaction is divided into sections

reactants and products

reactants on the left side of the reaction

products on the right side of the reaction

- All the symbols have a meaning

(s) means that that compound is in solid phase

(aq) means that that compound is dissolved in solution.

Then, the answer is CuSO₄

4 0

3 years ago