NEED HELP! FAST! WILL CHOOSE BRAINLIEST ANSWER!

Which of these is an example of a physical change?

Luda [366]

The answer is D) wood decaying

4 0

3 years ago

From the graph of Density vs. Concentration, created in Graph 1, what was the relationship between the concentration of the suga

USPshnik [31]

The graph is not given in the question, so, the required graph is attached below:

Answer:

According to the graph, the relationship between the density of the sugar solution and the concentration of the sugar solution is directly proportional to each other as they both are increasing exponentially.

The graph shows that, the density of sugar solution will increase with the increase in concentration of sugar in the solution.

8 0

3 years ago

For 2,663 kg of a compound with the formula Al(SO), determine the following quantities (4 pts each); a) The number of moles of t

Nastasia [14]

Answer:

a) 35.485 moles of Al(SO)

b) 35.485 moles of S atoms

c) $2.136197(10^{25})$ Al atoms

d) 567.723 g of O

Explanation:

Let's define the following terms :

1 mol = $6.02.(10^{23})$ elemental units

For example :

1 mol of oxygen atoms = $6.02.(10^{23})$ oxygen atoms

Now, our compound has the following formula

Al(SO)

Where Al is aluminium

S is sulfur

And O is oxygen

All the subscripts are 1 so we can say the following :

1 molecule of Al(SO) has 1 atom of Al , 1 atom of S and 1 atom of O

In terms of moles :

1 mol of Al(SO) has 1 mol of Al , 1 mol of S and 1 mol of O

The molar masses of Al, S and O are

$molarmass_{(Al)}=26.982\frac{g}{mol}$

$molarmass_{(S)}=32.065 \frac{g}{mol}$

$molarmass_{(O)}=15.999\frac{g}{mol}$

If we sum all the molar masses = $(26.982+32.065+15.999)\frac{g}{mol}=75.046\frac{g}{mol}$

Finally, 75.046 g of Al(S0) is 1 mol of Al(SO) which contains 26.982 g of Al, 32.065 g of S and 15.999 g of O.

1 mol of Al(SO) contains 1 mol of Al, 1 mol of S and 1 mol of O.

Now we can calculate a),b),c) and d)

For a)

$2.663 kg=2663g$

75.046 g of Al(SO) = 1 mol of Al(SO)

2663 g of Al(SO) = x

$x=\frac{2663}{75.046}mol=35.485 mol$

2.663 kg of Al(SO) contains 35.485 moles of Al(SO)

b) and c) 1 mol of Al(SO) molecules contains 1 mol of S atoms and 1 mol of Al atoms

We have 35.485 moles of Al(SO) molecules so

We have 35.485 moles of S atoms

And 35.485 moles of Al atoms

If 1 mol = $6.02(10^{23})$

35.485 moles of Al have $(35.485)(6.02)(10^{23})=2.136197(10^{25})$ Al atoms

d) 75.046 g of Al(SO) contains 15.999 g of O

2663 g of Al(SO) contains x g of O

$x=\frac{(2663).(15.999)}{75.046} g$

x = 567.723 g of O

6 0

3 years ago

The hall reaction of an oxidation-reduction reaction shows that iron gains electrons. What does this electron gain mean for iron

AnnZ [28]

Answer: Iron gains electrons mean It is reduced

Explanation:

Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.

Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.

$Zn\rightarrow Zn^{2+}+2e^-$

Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.

$Fe^{2+}+2e^-\rightarrow Fe$

Thus iron gains electrons mean It is reduced

6 0

3 years ago

A potassium hydroxide (KOH) solution has a molar concentration of 0.065 M, calculate the [H3O+], [OH-] and pH of the solution.

Tanya [424]

Answer:

1) [OH⁻] = 0.065 M

2) [H₃O⁺] = 1.54 x 10⁻¹³ M.

3) pH = 12.81.

Explanation:

HCl is completely dissociated yo its ions in solution:

KOH + H₂O → H₃O⁺ + K⁺ + OH⁻,

1) [OH⁻] = 0.065 M.

2) [H₃O⁺]:

∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.

∴ [H₃O⁺] = 10⁻¹⁴/[OH⁻] = 10⁻¹⁴/(0.065 M) = 1.54 x 10⁻¹³ M.

3) pH:

For strong acids like HCl:

pH = - log[H₃O⁺] = - log[1.54 x 10⁻¹³ M] = 12.81.

4 0

3 years ago