this is already solved but i would appreciate if someone check for me. thank you ! ​

Answer: The final temperature will be [tex]23^oC[/tex]

Explanation:

Calculating the heat released or absorbed for the process:

[tex]q=m\times C\times (T_2-T_1)[/tex]

In a system, the total amount of heat released is equal to the total amount of heat absorbed.

[tex]q_1=-q_2[/tex]

    OR

[tex]m_1\times C_1\times (T_f-T_1)=-m_2\times C_2\times (T_f-T_2)[/tex]           ......(1)

where,

[tex]C_1[/tex] = specific heat of aluminium = [tex]0.21 Cal/g^oC[/tex]

[tex]C_2[/tex] = heat capacity of water = [tex]1Cal/g^oC[/tex]

[tex]m_1[/tex] = mass of aluminium = 30. g

[tex]m_2[/tex] = mass of water = 50. g

[tex]T_f[/tex] = final temperature of the system = ?

[tex]T_1[/tex] = initial temperature of aluminium = [tex]40.^oC[/tex]

[tex]T_2[/tex] = initial temperature of the water = [tex]21.^oC[/tex]

Putting values in equation 1, we get:

[tex]30\times 0.21\times (T_f-40)=-50\times 1\times (T_f-21)\\\\56.3T_f=1302\\\\T_f=\frac{1302}{56.3}=23.13^oC=23^oC[/tex]

Hence, the final temperature will be [tex]23^oC[/tex]

Answer:

C. an element

Explanation:

Elements are pure substances and made up of only one type of atoms which cannot be further broken down.

Answer:

2NaOH + 2Al +2H2O = 2NaAlO2 +3H

Explanation:

Aluminum is an amphoteric element it reacts with both bases and acids to form a salt and hydrogen gas.The reaction is highly exothermic.

Answer:

Give an example of each of the following chemical changes.

(a) A photochemical reaction involving

(i) silver salt

(ii) water

(b) A reaction involving

(i) blue solution

(ii) formation of dirty green precipitate

(c) Two gases combine to form white solid.

(d) A reaction where colour change is noticed.​

Explanation:

a) A photochemical reaction involving  silver salt is used in black and white photography.

AgCl breaks down and converts into Ag during this photochemical reaction.

(ii) Photochemicalreaction involving water takes place in plants during the photosynthesis process.

Plants prepare food(carbohydrate) by using sunlight water and CO2 gas.

(b) A reaction involving

(i) blue solution:

For example reaction of copper sulfate solution with an iron nail.

When an iron nail is placed in CuSO4 blue color solution, then it changes to green color and reddish-brown solid deposits at the bottom of the container.

(ii) Reaction of ferrous sulfate with NaOH forms a dirty green precipitate of ferrous hydroxide.

(C) Two gases combine and form a white solid:

For example when HCl gas reacts with ammonia gas, then a white solid of ammonium chloride will be formed.

(d)  A reaction where the color change is noticed.:

When an iron nail is placed in CuSO4 blue color solution, then it changes to green color and reddish-brown solid deposits at the bottom of the container.

Answer:

Gain energy, move less, become closer together

Answer:

See explanation

Explanation:

Let the equation of dissolution be;

AB2(s) ⇄A(aq) + 2S

Hence;

Ksp = [A] [2s]^2

Let the concentration of the species be s

Ksp= s × (2s)^2

Ksp= 4s^3

Since s= 5mol/dm^3

Ksp = 4(5mol/dm^3)^3

Ksp = 500 mol^2dm^-6

Answer:

B

Explanation:

When the electron goes up levels it absorbs energy to enter that higher energy state. When it goes down, it releases energy but just not as much because 1-4 is more than 4-2.

Answer:b

Explanation:

I searched it

Answer:

The study of the interaction of electrical and magnetic fields, and their interaction with matter, is called Electromagnetism

Answer:

First oil well in the United States, built in 1859 by Edwin L. Drake, Titusville, Pennsylvania.

Answer:

JWBVH

Explanation:

NWSBWHSBHS

Answer: A 0.20 M solution of HCl with a volume of 15.0 mL is exactly neutralized by the 0.10 M solution of NaOH with 3 mL volume.

Explanation:

Given: [tex]M_{1}[/tex] = 0.20 M,      [tex]V_{1}[/tex] = 15.0 mL

[tex]M_{2}[/tex] = 0.10 M,            [tex]V_{2}[/tex] = ?

Formula used is as follows.

[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]

Substitute the values into above formula s follows.

[tex]M_{1}V_{1} = M_{2}V_{2}\\0.20 M ]times 15.0 mL = 0.10 M ]times V_{2}\\V_{2} = 30 mL[/tex]

Thus, we can conclude that a 0.20 M solution of HCl with a volume of 15.0 mL is exactly neutralized by the 0.10 M solution of NaOH with 3 mL volume.

Answer: The given compounds are arranged in order of increasing entropy (S) as [tex]CH_{3}OH(s) < CH_{3}OH(l) < CH_{3}CH_{2}OH < CH_{3}OH(g)[/tex]

Explanation:

The degree of randomness present in a substance is called entropy.

This means that more is the number of molecules weakly held together and rapidly moving from one place to another more will be its entropy.

In solids, the molecules are held together strongly with each other. So, they will have least entropy.

In liquids, the molecules are a little loosely held together. So, they have more entropy than a solid substance.

In gases, the molecules are held by weak forces due to which they move rapidly from one place to another. Hence, gases have high entropy as compared to solids and liquids.

Also, more is the molecular mass of a gas less will be its rate of effusion. Hence, less will be its entropy.

[tex]Rate of effusion \propto \frac{1}{\sqrt{M}}[/tex]

where,

M = molecular mass

Thus, we can conclude that given compounds are arranged in order of increasing entropy (S) as [tex]CH_{3}OH(s) < CH_{3}OH(l) < CH_{3}CH_{2}OH < CH_{3}OH(g)[/tex]

Answer:

yes and yes and yes and absolutely yes. Yes do it

Answer:

For a: The balanced equation is [tex]2S(s)+3O_2(g)\rightarrow 2SO_3(g)[/tex]

For c: The balanced equation is [tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)[/tex]

Explanation:

A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.

The given unbalanced equation follows:

[tex]S(s)+O_2(g)\rightarrow SO_3(g)[/tex]

To balance the equation, we must balance the atoms by adding 2 infront of both [tex]S(s)[/tex] and [tex]SO_3[/tex] and 3 in front of [tex]O_2[/tex]

For the balanced chemical equation:

[tex]2S(s)+3O_2(g)\rightarrow 2SO_3(g)[/tex]

The given balanced equation follows:

[tex]2Al(s)+3Cl_2(g)\rightarrow 2AlCl_3(s)[/tex]

The given equation is already balanced.

The given unbalanced equation follows:

[tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+H_2O(l)[/tex]

To balance the equation, we must balance the atoms by adding 2 infront of [tex]H_2O(l)[/tex]

For the balanced chemical equation:

[tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)[/tex]

The given balanced equation follows:

[tex]C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g)[/tex]

The given equation is already balanced.

Answer:

a solute

Explanation:

the answer is a solute

Answer:

Malleability describes the property of a metal's ability to be distorted below compression. It is a physical property of metals by which they can be hammered, shaped and rolled into a very thin sheet without rupturing. A malleable fabric could be planate by blow or rolling.

Explanation:

Ductility is the property of a solid, like a metal, to deform under a tensile stress (force). So if you pull on two ends of a metal wire or bar, and it “stretches” you have a ductile substance. Though I must caution that you don't confuse the definition of ductile to mean elastic. They are not synonyms. It is the opposite of brittle. When a ductile item breaks, it is after necking, where the diameter of the wire in question reduces as the length elongated. A brittle, or non-ductile material simple tears apart in a sharp and quick fashion with little to no visible necking taking place.

sonorous: producing sound (as when struck)

Answer:

D

hope it helps:)))!!!!!!

The concept Planck's quantum theory of radiation is used here to determine the wavelength of the light. The wavelength of the light with 4.01 x 10⁻¹⁹ J of energy is 496 nm . The correct option is B.

According to Planck's quantum theory, different atoms and molecules can emit or absorb energy in discrete amount only. The smallest amount of energy which can be emitted or absorbed in the form of electromagnetic radiation is called quantum.

The energy of the radiation absorbed or emitted is directly proportional to the frequency of the radiation. It is given by the equation:

E = hν

ν = E / h

4.01 x 10⁻¹⁹ J / 6.626 x 10⁻³⁴ = 6.05 × 10¹⁴ Hz

We have,

ν = c / λ

λ = c / ν

3.00 x 10⁸  /  6.05 × 10¹⁴ = 4.958 × 10⁻⁷ m

1 nm = 1 × 10⁻⁹ m

4.958 × 10⁻⁷ m = 495.8 nm = 496 nm

Thus the correct option is B.

To know more about wavelength, visit;

https://brainly.com/question/30171018

#SPJ7

Answer:

1.3 × 10²⁵ atoms

Explanation:

Step 1: Calculate the volume of an apple

The radius of an apple is 3.5 cm (3.5 × 10⁻² m). If we assume it is a sphere, we can calculate its volume using the following expression.

V = 4/3 × π × r³

V(apple) = 4/3 × π × (3.5 × 10⁻² m)³ = 1.8 × 10⁻⁴ m³

Step 2: Calculate the volume of 1 atom

The radius of 1 atom is 1.5 A (1.5 × 10⁻¹⁰ m). If we assume it is a sphere, we can calculate its volume using the following expression.

V = 4/3 × π × r³

V(atom) = 4/3 × π × (1.5 × 10⁻¹⁰ m)³ = 1.4 × 10⁻²⁹ m³

Step 3: Calculate how many atoms are in 1 apple.

V(apple)/V(atom) = 1.8 × 10⁻⁴ m³/1.4 × 10⁻²⁹ m³ = 1.3 × 10²⁵

Answer:B.  as a mineral is a deposit of fine materials it would not contain decayed materials without outside assistance

Answer:

Copper; Symbol is Cu

Protons = 29

Electrons = 29

Mass number = Protons + Neutrons

•°• Protons = Mass number - Neutrons

= (65-36)

= 29

Electrons is equal to the number of protons in a nucleus.

Answer:+5

Explanation: A P3X

Answer: The mass of [tex]FeO[/tex] required is 14.37 g

Explanation:

Molarity is calculated by using the equation:

[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)

We are given:  

Molarity of iron (II) sulfate = 1 M

Volume of solution = 200 mL = 0.200 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

[tex]\text{Moles of }FeSO_4=(1mol/L\times 0.200L)=0.200mol[/tex]

The chemical equation for the reaction of FeO with sulfuric acid follows:

[tex]FeO+H_2SO_4\rightarrow FeSO_4+H_2O[/tex]

By stoichiometry of the reaction:

If 1 mole of iron (II) sulfate is produced by 1 mole of FeO

So, 0.200 moles of iron (II) sulfate will produce = [tex]\frac{1}{1}\times 0.200=0.200mol[/tex] of FeO

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]

We know, molar mass of [tex]FeO[/tex] = 71.84 g/mol

Putting values in above equation, we get:

[tex]\text{Mass of }FeO=(0.200mol\times 71.84g/mol)=14.37g[/tex]

Hence, the mass of [tex]FeO[/tex] required is 14.37 g

Answer:

I believe it's a.

Explanation:

Answer: sorry its lagging i hope this help fore 18.. =D

Explanation:

n,s is repeating the cycle of the inside

Answer/Explanation:

18, a,

I believe the n, and s represents North, South, or just the way the arrows are rotating repeatedly.

18, b,

The phenomenon re-occurring shows the alignment of magnetic dipoles with in a magnet, like inside. The arrows show a direction in the line with an external magnetic field in a way that it can produce its own magnetic fields that seem to travel from North to the South.

18, c,

Incorrect. Refrigerator magnets have multiple layers of magnification, they use opposite polarities to stay this way. If he puts the magnet sideways it may stick to the fridge

~ LadyBrain

Answer:

5.1 moles of P2O3 are required

Explanation:

Based on the reaction, 1 mole of diphosphorus trioxide, P2O3, reacts with 3 moles of water to produce 2 moles of phosphorous acid, H3PO3. That means the conversion factor is: 1mol P2O3 = 2mol H3PO3.

The moles of P2O3 required to produce 10.2mol H3PO3 are:

10.2mol H3PO3 * (1mol P2O3 / 2mol H3PO3) =

The reaction that can be used to extract copper metal from copper sulfate solution would be equation 2.

Fe will displace Cu from CuSO4 because it is more reactive. In other words, Fe ranks higher than Cu in the reactivity series.

Thus:    [tex]Fe + CuSO_4 ---> Cu + FeSO_4[/tex]

Even though Na will displace Cu from CuSO4, equation 1 will result in the formation of Cu(OH)2 instead of free Cu because it is a double replacement reaction.

More on copper production can be found here: https://brainly.com/question/13677872?referrer=searchResults

Answer: -3112 kJ of heat will be released when 5 moles of nitrogen is produced.

Explanation:

We are given:

Moles of nitrogen = 5 moles

Given chemical reaction follows:

[tex]N_2H_4+O_2\rightarrow N_2+2H_2O;\Delta H=-622.4 KJ[/tex]

By stoichiometry of the reaction:

If 1 mole of nitrogen gas is produced, the heat released is -622.4 kJ

So, if 5 moles of nitrogen gas is produced, the heat released will be = [tex]\frac{-622.4kJ}{1mol}\times 5mol=-3112kJ[/tex]

Hence, -3112 kJ of heat will be released when 5 moles of nitrogen is produced.