Question 7 of 10
How much energy is required to melt 2 kg of aluminum? Use the table below
and this equation: Q- mLfusion
Substance
Latent Heat
Fusion
(melting)
(kJ/kg)
Melting
Point
(°C)
Latent Heat
Vaporization
(boiling) (kJ/kg)
Boiling
Point
("C)
Aluminum
400
660
1100
2450
Copper
207
1083
4730
2566
Gold
628
1063
1720
2808
Helium
5.2
-270
21
-269
Lead
245
327
871
1751
Mercury
11.4
-39
295
357
Water
335
0
2258
100
A. 2200 kJ
B. 800 kJ
C. 1600 kJ
D. 1100 kJ

Answer:

Dependent variable

Explanation:

In every experiment, there must be a dependent variable and an independent variable.

The independent variable is that variable that you have to manipulate in order to receive a response. E.g, in the experiment described in the question, the amount of sunlight a sunflower plant receives is the independent variable.

The dependent variable is the number of seeds produced. It is the response obtained by carefully manipulating the amount of sunlight

Answer:

i) During washing

ii) During Measurement

Explanation:

The two possible steps are :

i) During washing : during the washing method the residue may be not completely dried out and this residue ( water) will add up to the final product ( copper yield ) and this kind of error is called human error.

ii) During measurement : If the weighing instrument is faulty there might be addition  in value of the final copper yield which will see the final yield value > 100% . this error occurs when the initial value and final value is  been weighed

Answer:

CH3OH(s)<CH3OH(l)<CH3OH(g)<CH3CH2OH(g)

Explanation:

Entropy is defined as the degree of disorderliness of a system. The more orderly a system is, the more its entropy tends to zero.

Hence solid particles have the least entropy because solid particles do not translate. The entropy of liquid particles is greater than that of solid particles since liquid particles can translate. Gas particles have the highest entropy because gas particles move at a very high velocity owing to minimal intermolecular interaction.

Also, the heavier the molecules of a substance, the larger its molar entropy therefore, CH3CH2OH(g) exhibits the greatest entropy.

Answer:

Here's your answer

Explanation:

When we insert a burning matchstick near the mouth of gas jar the matchstick burns with a pop sound and produces a blue flame. This proves that the gas collected is hydrogen.

hope it helps

Answer:

A. Protons and electrons

Answer:

B. The wavelengths of light a molecule gives off when an electron moves to lower energy levels

Answer:

Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products.

A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Chemical reactions are an integral part of technology, of culture, and indeed of life itself. Burning fuels, smelting iron, making glass and pottery, brewing beer, and making wine and cheese are among many examples of activities incorporating chemical reactions that have been known and used for thousands of years. Chemical reactions abound in the geology of Earth, in the atmosphere and oceans, and in a vast array of complicated processes that occur in all living systems.

Explanation:

hope it help

plss brainlys me

Answer:

Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products

Explanation:

Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Answer:

Our energy supply comes mainly from fossil fuels, with nuclear power and renewable sources rounding out the mix.

The energy associated with an object's motion is called kinetic energy. Kinetic energy is the energy of motion. All moving objects have kinetic energy

Explanation:

Answer:

Kinetic energy is the energy of motion. All moving objects have kinetic energy. When an object is in motion, it changes its position by moving in a direction: up, down, forward, or backward. As he winds up and releases the ball, the stored energy is changed into kinetic energy, the energy of motion!So that , energy comes from and how it is affecting change or putting an object in motion.

Explanation:

I ain't flashligh

Answer: A pattern of same atomic orbitals can be seen about elements in the same period with respect to electron structures.

Explanation:

The horizontal rows in a period table are called periods.

Elements present in the same period will have same atomic orbitals.

For example, electronic distribution of Na is 2, 8, 1 and it is a third period element.

Similarly, electronic distribution of Cl is 2, 8, 7 and it is also a third period element.

Hence, both Na and Cl will have K, L, M shells, that is, they have three atomic orbitals.

Thus, we can conclude that a pattern of same atomic orbitals can be seen about elements in the same period with respect to electron structures.

Answer:

D).

[tex]{ \tt{NO_{3} {}^{ - } }}[/tex]

Explanation:

The nitrate ion because it is a radical with a valence of 1, forming sodium nitrate.

[tex]{ \tt{Na {}^{ + } .NO _{3} {}^{ - } }}[/tex]

The polyatomic ion that does form an ionic compound with a single sodium ion (Na^+) is NO3^- .

A polyatomic ion is an ion that contains more than one atom. Recall that an ion is any chemical specie that contains a positive or negative charge. Sodium is a member of group 1 and forms a univalent positive ion.

The polyatomic ion that does form an ionic compound with a single sodium ion (Na^+) is NO3^- and the compound is NaNO3.

Learn more: https://brainly.com/question/8592296?

Answer:

protons because they have the most positive charge

Answer:

a pure substance consists only of one element or one compound. a mixture consists of two or more different substances, not chemically joined together.

Explanation:

Radhe Radhe❤

Answer:

A pure substance consists of only one element or one compound. Whereas, a mixture consists of two or more different substances which aren't chemically joined together.

Answer:

1.63 × 10²⁴ atoms.

Explanation:

To calculate the number of atoms (N) contained in 2.7moles of carbon, we multiply the number of moles (n) by Avogadro's number (6.02 × 10²³).

That is, N = n × nA

Where;

N = number of atoms

n = number of moles (mol)

nA = Avogadro's numbe

N = 2.7 × 6.02 × 10²³

N = 16.254 × 10²³

N = 1.63 × 10²⁴ atoms.

Hence, there are 1.63 × 10²⁴ atoms in 2.7moles of Carbon.

Answer:

A) Very stable.

Explanation:

A valence electron ring takes up to 8 valence electrons. If it has full rings, it is stable.

Answer:(d) has a high melting point because it has a giant covalent structure ... (i) Calculate the maximum mass of propyl ethanoate that can be made from 7.20 g of ethanoic ... (c) Anhydrous aluminium chloride contains 20.2% by mass of aluminium. (i) Show that the empirical formula for anhydrous aluminium chloride is A

Explanation:

Answer:

bleh

Explanation:

Neutralization reaction between magnesium hydroxide and hydrochloric acid Mg(OH)2(s) + 2HCl(aq) → 2H2O(l) + MgCl2(aq) b.

so uh pretty sure Mg(OH)2(s) + 2HCl(aq) → 2H2O(l) + MgCl2(aq) b.

correct me if im wrong <3

Answer:1.205g

Explanation:

Answer:

12:35

Try it this way. egst11245

Answer:

A is mixture

B and C are compund

D and E are elements

F is also mixture

About 4/5.

Hope this helps.

Answer:  c

Explanation:

Answer:

Elements that have atomic numbers from 20 to 83 are heavy elements, therefore the ratio is different. The ratio is 1.5:1, the reason for this difference is because of the repulsive force between protons: the stronger the repulsion force, the more neutrons are needed to stabilize the nuclei.

Answer:

Mole of NaOH = 0.00308 mole

Explanation:

From the question given above, the following data were obtained:

Volume = 22 mL

Molarity = 0.140 M

Mole of NaOH =?

Next, we shall convert 22 mL to L. This can be obtained as follow:

1000 mL = 1 L

Therefore,

22 mL = 22 mL × 1 L / 1000 mL

22 mL = 0.022 L

Finally, we shall determine the number of mole of NaOH in the solution. This can be obtained as shown below:

Volume = 0.022 L

Molarity = 0.140 M

Mole of NaOH =?

Molarity = mole / Volume

0.140 = Mole of NaOH / 0.022

Cross multiply

Mole of NaOH = 0.140 × 0.022

Mole of NaOH = 0.00308 mole

Thus, 0.00308 mole of NaOH is present in the solution.

Answer:

red blood cells and diffusion.

Explanation:

this process involves red blood cells and diffusion. Red Blood cells (RBCs) are a type of blood cell whose role is to transport oxygen from the lungs to the peripheral tissues of the body. Oxygen diffuses from the alveoli of the lungs in to the RBC's, where it binds to hemoglobin.

Diffusion is a very important process within the human body and is essential to the transport of molecules within a number of organs including the lungs, kidneys, stomach and eyes. The lungs process millions of tiny air sacs that are called alveoli, each of which are in close contact with capillaries.

Complete Question

4. A piece of metal weighing 0.0713 g was placed in a eudiometer containing dilute aqueous HCl. After the metal fully dissolved, 23.5 mL of hydrogen gas was collected by displace-ment of water and a 400 mm column of water was observed. The water temperature was 258C and the barometric pressure was 758.8 mm Hg (torr). Refer to the Introduction and data sheet to solve the following problems.

a) What is the vapor pressure of the water vapor in the column? (Consult Appendix E.)

b) What is the pressure of the water column expressed in mm Hg (torr)? The density of mercury is 13.6 g/mL.

c) Calculate the pressure of the hydrogen gas above the water in the column.

d) Calculate the volume occupied by the hydrogen gas at STP.

Answer:

a)  [tex]25\textdegree C=23.8 torrs[/tex]

b) [tex]P_w=758.8[/tex]

c)  [tex]P_w=758.8=735torr[/tex]

d)  [tex]V_2=20.82mL[/tex]

Explanation:

From the question we are told that:

Metal weight [tex]M_m=0.0713g[/tex]

Volume Hydrogen [tex]V_h=23.5mL[/tex]

Displace-ment Column of water 400 mm column of water

Temperature [tex]T =258\textdegree C[/tex]

Barometric Pressure [tex]p=758.8mmHg[/tex]

Vapour Pressure of water at [tex]25^oC[/tex]

Generally from (Consult Appendix E.)

a)

Va-pour Pressure of water at

[tex]25\textdegree C=23.8 torrs[/tex]

b)

Pressure of Water column

[tex]P_w=758.8[/tex]

c) Pressure of Water column (Consult Appendix E.)

[tex]P_w=758.8=735torr[/tex]

d)

Generally the equation for ideal gas is mathematically given by

 [tex]\frac{p_1v_1}{T_1}=\frac{p_2v_2}{T_2}[/tex]

Therefore

 [tex]V_2=\frac{p_1V_1T_2}{T_1p_2}[/tex]

 [tex]V_2=\frac{735*23.5*273}{298*760}[/tex]

 [tex]V_2=20.82mL[/tex]

Answer:

4084.808 grams (SigFigs: 4085 grams)

Explanation:

The molar mass of Iron fluoride is 112.84 g/mol.

To calculate the mass, multiply the molar mass by the number of moles.

36.2 mol * 112.84 g/mol = 4084.808 g

Convert to Sigfigs (if necessary):

4085 g

Answer:

The person above is correct

Explanation:

1. [tex]\sf \bf {\boxed {\mathbb {Evaporation}}}[/tex] - The changing of liquid to a gas.

2. [tex]\sf \bf {\boxed {\mathbb {Automobile}}}[/tex] - The major source of pollution.

3. [tex]\sf \bf {\boxed {\mathbb {Greenhouse \:effect}}}[/tex] - Carbon dioxide and water vapor trapping heat given off by Earth.

4. [tex]\sf \bf {\boxed {\mathbb {Ozonosphere}}}[/tex] - Layer absorbing ultraviolet rays.

5. [tex]\sf \bf {\boxed {\mathbb {Condensation}}}[/tex] - The changing of a gas to a liquid.

6. [tex]\sf \bf {\boxed {\mathbb {Ionosphere}}}[/tex] - Layer responsible for reflecting radio waves.

7. [tex]\sf \bf {\boxed {\mathbb {Troposphere}}}[/tex] - The layer in which weather changes.

[tex]\large\mathfrak{{\pmb{\underline{\orange{Mystique35 }}{\orange{❦}}}}}[/tex]

Answer:

1. Evaporation :- The changing of a liquid to a gas.

2. Automobile :- The major source of pollution.

3. Greenhouse effect :- Carbon dioxide and water vapour trapping heat gives off by Earth.

4. Ozonosphere :- Layer absorbing ultraviolet rays.

5. Condensation :- The changing of gas to a liquid.

6. Ionosphere :- Layer responsible for reflecting radio waves.

7. Troposphere :- The layer in which weather changes.

Answer:

a.endothermic reaction

Answer:

See explanation

Explanation:

Let us recall that the basic rule in writing balanced chemical reaction equations is that the number of atoms of each element on the right hand side of the reaction equation is the same of the number of atoms of the same element on the left hand side of the reaction equation.

The reaction of red hot iron and steam is written as follows;

3Fe + 4H2O → Fe3O4 + 4H2.

The decomposition reaction of ammonium dichromate is written as;

(NH4)2Cr2O7 → N2 + Cr2O3 + 4H2O

Reaction of aluminium, sodium hydroxide and water is as follows,

2Al + 2NaOH + 2H2O ----> 2NaAlO2 + 3H2

Reaction of potassium bicarbonate with sulphuric acid;

2KHCO3 + H2SO4 -------> K2SO4 + 2H2O + 2CO2

Reaction of zinc and sodium hydroxide is as follows;

Zn + 2NaOH→Na2ZnO2 + H2