Answer:
The difference between a physical reaction and a chemical reaction is what its made of. In a chemical reaction, there is a change in the materials of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Whereas will a chemical change there is not.
Answer:
Answer:
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds. Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. Some signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change. Change in Color. Noticeable Odor (after reaction has begun) Formation of a Precipitate. Formation of Bubbles. Physical changes are changes that do not alter the identity of a substance. Chemical changes are changes that occur when one substance is turned into another substance. Chemical changes are frequently harder to reverse than physical changes
Explanation:
Determine the empirical formula for compounds that have the following analyses. a. 28.4% copper, 71.6% bromine b. 39.0% potassium, 12.0% carbon, 1.01% hydrogen, and 47.9% oxygen c. 77.3% silver, 7.4% phosphorus, 15.3% oxygen d. 0.57% hydrogen, 72.1% iodine, 27.3% oxygen
Answer:
See explanation
Explanation:
Cu- 28.4/63.5, Br- 71.6/80
Cu- 0.447/0.447, Br- 0.895/0.447
Cu- 1, Br - 2
Empirical formula = CuBr2
b)
K- 39.0/39, C-12.0/12, H- 1.01/1, O- 47.9/16
K= 1, C-1, H- 1. O-3
Empirical formula= KHCO3
c)
Ag- 77.3/108, P-7.4/31, O-15.3/16
Ag-0.716/0.239, P- 0.239/0.239, O-0.956/0.239
Ag-3, P-1, O-4
Empirical formula= Ag3PO4
d)
H-0.57/1, I- 72.1/127, O-27.3/16
H- 0.57/0.57, I- 0.57/0.57, O-1.71/0.57
H-1, I-1, O- 3
Empirical formula= HIO3
The number of joules required to heat one gram of a substance one degree Celsius is _____.
endothermic
temperature
exothermic
specific heat capacity
Which phrase correctly describes the molecular structure within a molecule?
Same molecular structure and same properties.
Molecular structure is three dimensional structure in which arrangement of atoms is placed.
The molecular structure of a compound determines the polarity and its reactivity.
The different states of matter solid, liquid and gas have different molecular structure and different properties from each other.
The molecular structure of a molecule will have same properties as of the entire molecule based on its state.
Learn more at https://brainly.com/question/24325752
Answer:
the location of atoms, groups, or ions relative to one another and the number, type, and location of covalent bonds
The boiling points of diatomic halogens are compared in the table.
Boiling Points of Diatomic
Halogens
Molecule
Boiling Point
F2
-188 °C
Cl2
-34 °C
Br2
59 °C
12
184°C
Which of the following statements best explains the trends in boiling points?
The atomic size increases down the group, and this decreases the strength of the intermolecular forces.
The total number of electrons decreases down the group, and this decreases the strength of the intermolecular forces.
The total number of electrons increases down the group, and this increases the strength of the intermolecular forces.
The chances of forming a permanent dipole increases down the group, and this increases the strength of the intermolecular forces.
Which of the following statements best explains the trends in boiling points?
A. The atomic size increases down the group, and this decreases the strength of the intermolecular forces.
A is incorrect
B. The total number of electrons decreases down the group, and this decreases the strength of the intermolecular forces.
B is incorrect
C. The total number of electrons increases down the group, and this increases the strength of the intermolecular forces.
C is correct
D. The chances of forming a permanent dipole increases down the group, and this increases the strength of the intermolecular forces.
D is incorrect
The boiling point increase down a group because the total number of electrons increases down the group, and this increases the strength of the intermolecular forces. Hence option C is correct.
What is boiling point?Boiling point of a substance is the temperature at which the substance changes from its liquid state to vapour state. Boiling point of a molecule or compounds depends on the bond type, molecular weight, temperature and pressure.
For ionic compounds, boiling point will be higher since ionic bonds are stronger than covalent compounds. There is a periodic trend for the physical properties such as boiling point for elements in periodic table.
Down a group, the number of electrons increases and the atomic size also as well as the ionic character increases down a group . These two facts leads to higher intermolecular attraction, thus more temperature have to applied to weaken the bonds.
Higher temperature to be applied means the boiling point of the substance is higher. Therefore, boiling point down a group increases because of the higher intermolecular attraction as said in option C.
To find more about boiling point, refer the link below:
https://brainly.com/question/2153588
#SPJ1
3. A typical peanut butter and jelly sandwich contains 360 kcal, of which 160
kcal comes from fat. Given 1 kcal = 4.2 kJ, how many J of fat would there be
in one PB&J sandwich?
Explanation:
here's the answer to your question
which is the answer?
Answer:
I could be wrong letter c
which state of matter expands most when heated
Answer:
Gases expand the most upon heating because the intermolecular space is more than in solids or liquids.
Explanation:
hopes it helps
What is an atomic mass unti
Explanation:
a unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.
Answer:
Atomic Mass Unit is also called Dalton. It is used to express atomic and molecular weight. It is defined as 1/12 of the mass of an unbound neutral atom of carbon.
What is the AHsol for LiF → Lit + F-? The lattice energy is -1,036 kJ/
mol, the enthalpy of hydration for Lit is -499
kJ/mol, and the enthalpy of hydration for F-is-431 kJ/mol. Use A Hooi = -A Hat + AHhydr.
0-968 kJ/mol
-106 kJ/mol
106 kJ/mol
1,966 kJ/
mol
The heat of hydration is defined as the heat absorbed or evolved when one mole of a substance undergoes hydration. The heat of solution is the enthalpy change associated with he dissolution of a solute. The lattice energy is the heat. Lattice energy is the energy released when the components of the lattice are brought together from infinity.
Hence the heat of solution for LiF → Li^+ + F- is -1966 kJ/mol
Given that;
Heat of hydration = ΔH solution – ΔH lattice energy
Where,
ΔH solution = Heat of the solution
ΔH lattice energy = Lattice energy of the solution
The heat of solution or enthalpy of dissolution is defined as the enthalpy change associated with the dissolution of a solute in a solvent
From the formula above;
ΔH solution = Heat of hydration + ΔH lattice energy
Heat of hydration = [(-431) + (-499)] = -930 kJ/mol
ΔH solution = (-930) + (-1,036) = -1966 kJ/mol
Hence the heat of solution for LiF → Li^+ + F- is -1966 kJ/mol
https://brainly.com/question/13526282
What will happen if we drink liquid nitrogen?
what is the reactant(s) in the chemical equation below
3CO(g) + Fe2O3(s) 2Fe(s) + 3CO2(g)
Answer:
the reactants are carbon dioxide ,iron, oxygen
Predict the approximate Ksp of Cuz(AsO4)2 based on the measured potential of Cell 7. Use the equation given in the Background.
a. 1 x 10^-35
b. 4 x 10^14
c. 5 x 10^-17
d. 2 x 10^-21
Answer:
a. 1 x 10^-35
Explanation:
The correct compound given is: [tex]\mathsf{Cu_3(AsO_4)}_2[/tex]
To predict the approximate Ksp value of the given compound, we will need to express the oxidation-reduction half-reaction of the compound and its dissociation, then, we will use the Nernst equation to determine the approximate Ksp value.
To start with the reduction half-reaction:
[tex]\mathsf{Cu_3(AsO_4)_{2}(s) + 6e^- \to 2As O_{4}^{3-}_{(aq)}+3Cu(s) }[/tex]
The oxidation half-reaction is:
[tex]\mathsf{3Cu(s) \to 3CU^{2+}_{(aq)} + 6e^-}[/tex]
The overall cell reaction now is:
[tex]\mathsf{Cu_3(AsO_4)_{2}(s) \to 3Cu^+ (aq) + 2As O_{4}^{3-}_{(aq)} }[/tex]
From the reduction half-reduction, the number of moles of electrons (n) transferred is 6 moles.
By applying the Nernst equation:
[tex]\mathsf{E_{cell} = E^0_{cell} -\dfrac{0.0591V}{n}log [Cu^{2+}]^3[AsO_4^{3-}]^2 }[/tex]
At standard conditions;
The standard cell potential [tex]\mathsf{E^0_{cell} = -0.342 \ V}[/tex]
and [tex]\mathsf{E_{cell} = 0 \ V}[/tex] since it is at equilibrium.
∴
[tex]\mathsf{0 = -0.342 -\dfrac{0.0591V}{6}log [Cu^{2+}]^3[AsO_4^{3-}]^2 } \\ \\ \\ \mathsf{0.342 = -\dfrac{0.0591V}{6}log [Cu^{2+}]^3[AsO_4^{3-}]^2 }[/tex]
[tex]\mathsf{log [Cu^{2+}]^3[AsO_4^{3-}]^2 = \dfrac{-(0.342)*6}{0.0591 }}[/tex]
[tex]\mathsf{log [Cu^{2+}]^3[AsO_4^{3-}]^2 = -34.7}[/tex]
[tex]\mathsf{log [Cu^{2+}]^3[AsO_4^{3-}]^2 \simeq -35}[/tex]
[tex]\mathsf{[Cu^{2+}]^3[AsO_4^{3-}]^2 = 10^{-35}}[/tex]
[tex]\mathbf{K_{sp} = [Cu^{2+}]^3[AsO_4^{3-}]^2 = 1\times 10^{-35}}[/tex]
PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ PLZ HELP ME......
Answer:
a) clockwise
b) clockwise and
c) anticlockwise
Using these metal ion/metal standard reduction potentials calculate cell potential for Cu2+(aq) + Cd(s) →Cd2+(aq)+ Cu(s) Cu2+(aq)|Cu(s) + 0.34 VNi2+(aq)|Ni(s) -0.25 Cd2+(aq)/Cd(s) -0.4V
Solution :
Cd(s) ----------------------> [tex]Cd^{+2}[/tex] (aq) + 2[tex]e^-[/tex] , [tex]E_0[/tex] = 0.34 v
[tex]Cu^{+2}[/tex] (aq) + 2[tex]e^-[/tex] ------------> Cu (s) , [tex]E_0[/tex] = -0.04 v
----------------------------------------------------------------------------------------------
Cd(s) + [tex]Cu^{+2}[/tex] (aq) -------------> [tex]Cd^{+2}[/tex] (aq) + Cu (s) , [tex]E_0[/tex] = 0.30 v
The cell potential is defined as the measure of [tex]\text{ potential difference }[/tex] between the [tex]\text{two half cells}[/tex] of an electrochemical cell.
"Every action force creates a reaction force that is equal in strength and opposite in direction." This statement summarizes Newton's
Answer: Newton's Third Law of Motion.
Explanation:
Newton's Third Law of Motion simply states that every action force creates a reaction force and then, this reaction force will be equal in strength and opposite in direction.
The statement simply implies that in every interaction, there will be a pair of forces that is acting on the two interacting objects. An example of Newton's third law of motion can be seen when a person jumps, thenlegs of the person will apply a force to the ground which will then propel the person into the air.
Which factor would speed up a chemical reaction? (Choose all that apply)
Decreasing particle size
Increasing the temperature
Decreasing the temperature
Increasing particle size
Answer:
Increasing the temperature
Increasing particle size
Explanation:
Increasing the temperature allows for particles and molecules to move faster (because there is an increase in energy) and allows for more collisions.
∴ Increasing the temperature would be an answer.
Increasing the particle size allows for more surface area and a greater chance for particles to collide with each other.
∴ Increasing particle size would be an answer.
Topic: AP Chemistry
Unit: Kinetics
Which of the following are held together by nonpolar covalent bonds?
The Periodic Table
A. Atoms of phosphorus (P) and chlorine (CI)
B. Atoms of chlorine (CI)
C. Atoms of chlorine (CI) and magnesium (Mg)
D. Atoms of magnesium (Mg)
Answer:
Answer: Atoms of chlorine (CI) and magnesium (Mg)
Answer: Atoms of chlorine (CI) and magnesium (Mg)is your answer
How many moles of oxygen are required to react completely with 5 mol C8H18?
Answer:
62.5 moles of O₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2C₈H₁₈ + 25O₂ —> 16CO₂ + 18H₂O
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Finally, we shall determine the number of mole of O₂ needed to react with 5 moles of C₈H₁₈. This can be obtained as shown below:
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Therefore, 5 moles of C₈H₁₈ will react with = (5 × 25) / 2 = 62.5 moles of O₂.
Thus, 62.5 moles of O₂ is needed for the reaction.
hii pls help me to balance the equation thanksss
Answer:
2H2S (g) + 3O2 (g) = 2H2O (l) + 2SO2 (g)
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
[tex]\boxed{\pmb{\green{\sf{2H_{2}S(g) + 3O_{2}(g)\dashrightarrow 2H _{2}O(l)+2SO_{2}(g)}}}}[/tex]
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
what is second explain it briefly
Explanation:
it is that when an object is moving 25 m per sec to calculate its time we can simply divide 1.5 by 25 and multiply by 1
giúp tớ với, mình học lớp 9 ạ
Answer: broooo what is this
Explanation:
what do y’all do when y’all brainly says “locked” and won’t show anymore answers !???
Answer:
Create a new account as the thing you're experiencing now is due to the fact that Brainly had blocked your account.
PLZ HELP ME A girl throws a ball and her dog chases it. What characteristic of living things is this dog demonstrating as it chases the ball?
A. Cells
B. Reproduction
C. Growth
D. Response
name some examples of chemical solutions and maybe give a clear explanation as to what chemical solutions are
Answer:
Some examples of solutions are salt water, rubbing alcohol, and sugar dissolved in water. ... In our example of salt water, the solute is the salt. Solvent: this is the substance that makes up the majority of the solution. This is the part where the solute is dissolved.
Explanation:
I hope they should be right answer
I need help on this question asap!
You are in a lab and you use 11.50 g of Na(s) to react with Cl(g). Below is the reaction that happens from this.
Na + Cl2 → NaCl
Your percent yield is 95%. From this info what is the actual yield?
Answer:
27.79 g to the nearest hundredth.
Explanation:
2Na + Cl2 ---> 2NaCl
Using the molar masses , the theoretical yield is:
46 g of Na yields 46 + 35.5*2 g NaCl
46 g ---> 117 g NaCl so
11.5 g ----> 117 * 11.5 / 46 g NaCl
But, as the yield is 90%
the actual yield is 0.95 * 117 * 11.5 / 46
= 27.79 g.
hii pls help me to balance the equation and state the symbols thanksss
Answer:
I hope that the link above will be helpful
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
[tex]\boxed{\pmb{\green{\sf{2Mg +H_{2}SO_{4}\dashrightarrow H _{2}+Mg_{2}SO_{4}}}}}[/tex]
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
What is the answer to 9.7300x10^2+9.8700x 10^3 1.0843x 10^ in scientific notation
Explanation:
Your search - What is the answer to 9.7300x10^2+9.8700x 10^3 1.0843x 10^ in scientific notation - did not match any documents.
Suggestions:
Make sure that all words are spelled correctly.
Try different keywords.
Try more general keywords.
Try fewer keywords.
26. Calculate the mass of hydrogen formed when 25 grams of aluminum reacts with excess hydrochloride acid. 2AI + 6HCl →l Al2Cl6 + 3H2
Answer:
2.76 gram
Explanation:
2AI + 6HCl → 2AlCl3 + 3H2
get the mol of aluminum => n = m / M = 25 / 27 = 0.925 (mol)get the ratio mol of Hydro => nH2 = 0.925 * 3 / 2 = 1.38 (mol)get weight of hydro mH2 = n x M = 1.38 x 2 = 2.76 (gram)Answer
Al +2 HCl - AlCl2 + H2
How many moles of Cd and of N are contained in 132.4 g of Cd(N03)2-4H20? (b) How many molecules of water of hydration are in this same amount?
Answer: The given amount of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 0.430 moles of Cd, 0.860 moles of N and [tex]2.59\times 10^{23}[/tex] molecules of water.
Explanation:
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] ......(1)
Given mass of [tex]Cd(NO_3)_2.4H_2O[/tex] = 132.4 g
Molar mass of [tex]Cd(NO_3)_2.4H_2O[/tex] = 308.5 g/mol
Plugging values in equation 1:
[tex]\text{Moles of }Cd(NO_3)_2.4H_2O=\frac{132.4g}{308.5g/mol}=0.430 mol[/tex]
1 mole of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 1 mole of Cd, 2 moles of nitrogen atom (N), 10 moles of oxygen atom (O) and 8 moles of hydrogen atom (H).
So, 0.430 moles of [tex]Cd(NO_3)_2.4H_2O[/tex] will contain = [tex](1\times 0.430) = 0.430mol[/tex] of Cd and [tex](2\times 0.430)=0.86mol[/tex] of N
According to the mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of molecules
So, 0.430 moles of [tex]Cd(NO_3)_2.4H_2O[/tex] will contain = [tex]\frac{6.022\times 10^{23}}{1mol}\times 0.430mol=2.59\times 10^{23}[/tex] number of water molecules.
Hence, the given amount of [tex]Cd(NO_3)_2.4H_2O[/tex] contains 0.430 moles of Cd, 0.860 moles of N and [tex]2.59\times 10^{23}[/tex] molecules of water.
What is a weak acid?
A. An acid that does not have a conjugate base
B. An acid that does not dissolve completely
C. An acid that has been diluted with water
D. An acid that has a very low pH value
Answer:
B
Explanation:
strong acids ionize completely in water
Answer:
An acid that does not dissolve completely
Explanation:
