Answer:
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17. (1.09 x 102) x (2.79 x 10')
18. (5.75 x 104) / (4.71 102)
19.(3.38 x 106) x (7.80 x 104)
20. (7.04 x 10) / (9.45 x 10-)
Answer:
17. 3,101.922
18. 1.2447441822
19. 288,057.12
20. 0.74497354
Describe the nucleus of an atom in short
Answer:
The nucleus is a small, region at the center of the atom which consists of protons and neutrons.
More Detailed Answer:
The nucleus is a small, dense region at the center of the atom. It consists of positive protons and neutral neutrons, so it has an overall positive charge. The nucleus is just a tiny part of the atom, but it contains virtually all of the atom's mass.
- flexbooks
How many liters does 3 moles of Oxygen gas occupy at standard temperature and pressure
Answer: 3 moles of oxygen at STP will occupy a volume of 3×22. 4=67. 2 L.
SOMEONE HELP ASAP I NEED TO FIND AN ANSWER
Answer:
A) Q + XZ = X + QZ is a single displacement reaction.
B) Q + Z = QZ is a synthesis reaction
C) QT = Q + T is a decomposition reaction
D) QT + XZ = QZ + XT is double replacement reaction.
Explanation:
A) Q + XZ = X + QZ
This is a single displacement reaction because it is one in which one element is substituted for another one in a compound. In this case X is substituted for Q.
B) Q + Z = QZ
This is a synthesis reaction because Q and z combine to form a single product QZ.
C) QT = Q + T
This is a decomposition reaction because the compound QT breaks down to form 2 simpler substances Q and T.
D) QT + XZ = QZ + XT
Thus is a double replacement reaction because QT and XZ have exchanged cations to form new compounds QZ and XT
Heavy rains fill a reservoir, causing the dam that holds the water to break. As a result, the areas downstream are suddenly flooded. Which question would a scientist seek to answer?
Answer:
"How to prevent the collapse of the dam that contains water from heavy rains?"
Explanation:
Scientists must work to create innovations capable of bringing benefits to human life and combating disadvantageous and harmful situations. The overflow of dams is something very harmful, as the resulting flooding can cause structural, economic and even public health problems. When this overflow is caused by natural elements, such as heavy rains, the work of scientists in solving these issues is even more important and necessary. In order to resolve the dam failure caused by excess rainwater, scientists must work to answer the following question:
"How to prevent the collapse of the dam that contains water from heavy rains?"
How does the process of cell division replace damaged cells
Cells split into two new cells with the identical genetic make up
Chloroplasts use carbon dioxide and water to create glucose
Metatron Gia uses oxygen to break down glucose and convert it to ATP
Waste passes through the cell membrane and leaves the cell
Answer:
A
Explanation:
The cells split up into two to repair the damaged cell
Need help asap!
What is the oxidation number of Chromium in Cr2O74-?
There are seven oxygen atoms, so the total charge is −2⋅7=−14 . So, two chromium atoms have a total oxidation number of +12 . Since one is not more electronegative than the other, we can divide the number by two to get one chromium's oxidation number. So, a chromium atom here has an oxidation number of +6 .
Hope it helps you I'm from ph❤️
2 A. Explain why these elements are all placed in Period 3 of the Periodic Table.
Answer:
which elements??? more info please
Can anyone plz explain me this
Answer:
A. Cl2(g) + 2NaBr(aq) --> 2NaCl(aq) + Br2(g)Explanation:
This is because,
Chlorine atoms (Cl2) displaces with Bromine atoms (Br) in Sodium bromide (2NaBr) solution to give a result as, Sodium Chloride (2NaCl) and left out atom Bromine (Br)
8. In a chemical reaction, if the reactants are heated, the reaction usually
happens a) Faster
b) Slower
c) At the same rate
the reaction usually happens faster
According to the kinetic-molecular theory, the average kinetic energy of gas particles depends on which factor?
Answer:
Temperature.
Explanation:
Kinetic molecular theory of gases states that gas particles exhibit a perfectly elastic collision and are constantly in motion.
According to the kinetic-molecular theory, the average kinetic energy of gas particles depends on temperature.
This ultimately implies that, the average kinetic energy of gas particles is directly proportional to the absolute temperature of an ideal gas. Thus, an increase in the average kinetic energy of gas particles would cause an increase in the absolute temperature of an ideal gas.
Temperature can be defined as a measure of the degree of coldness or hotness of a physical object. It is measured with a thermometer and its units are Celsius (°C), Kelvin (K) and Fahrenheit (°F).
What is the equilibrium expression for the reaction below?
2Na(s) + 02) Na2O2,(s)
Answer:
[tex]{ \tt{k _{c} = \frac{[Na_{2} O _{2} ]}{[Na] {}^{2} [O _{2} ]} }}[/tex]
Which statements are true of the reaction below? 2Na(s) + Cl2(g) ---> 2NaCl(s)

A.
Na(s) is a reactant.

B.
NaCl is a product.

C.
NaCl is a liquid.

D.
Cl2 is a solid.
Answer:
A and B are both true
Explanation:
Na is REACTING with Cl2 to PRODUCE NaCl
Which of the following is true of science?
O It can be disproven by philosophy and religion.
O It does not change after new evidence is discovered.
O It is based on the personal opinions of scientists.
O It is based on testable and replicable evidence.
Answer:
I know the other person already said this but it would be the last option : )
The equilibrium constant (K) for the reaction
2HCI(g) = H2(g) + Cl2(g)
is 4.17 x 10-34 at 25°C. What is the equilibrium constant for the reverse reaction at the same
temperature?
H2(g) + Cl2(g) = 2HCl(g)
Answer: The equilibrium constant for the reverse reaction at the same temperature is [tex]2.40 \times 10^{33}[/tex].
Explanation:
The given reaction equation is as follows.
[tex]2HCl(g) \rightleftharpoons H_{2}(g) + Cl_{2}(g)[/tex] ... (1)
It's equilibrium constant (K) value is [tex]4.17 \times 10^{-34}[/tex].
Also, another reaction equation is as follows.
[tex]H_{2}(g) + Cl_{2}(g) \rightleftharpoons 2HCl(g)[/tex]
This is the reverse of equation (1). Hence, its equilibrium value is calculated as follows.
[tex]K' = \frac{1}{K}\\= \frac{1}{4.17 \times 10^{-34}}\\= 2.40 \times 10^{33}[/tex]
Thus, we can conclude that the equilibrium constant for the reverse reaction at the same temperature is [tex]2.40 \times 10^{33}[/tex].
If you increase the amount of Reactant A, the reaction rate will also increase.
What is this statement an example of?
A. A theory
B. An observation
C. A hypothesis
D. A scientific question
Example of fundamental units?
Answer:
are the units of the fundamental quantities, as defined by the International System of Units
Explanation:
because
Roundup, a herbicide manufactured by Monsanto, has the formula C3H8NO5P. How many moles of molecules are there in a 647.3-g sample of Roundup?
I got the answer 2.305 x 10^24 but for some reason it’s not working. Is it the wrong one?
Answer:
3.830177515 moles
Explanation:
You have :
647.3 g of RoundupMolar mass of Round up which is equal to 169 g.moland the formula: n=m/MTherefore: n=647.3/169
=3.830177515 moles
What is a reaction rate
Answer:
Explanation:
A reaction rate is the measure of the change in concentration of the disappearance of reactants or the change in concentration of the appearance of products per unit time
The half-reaction at the cathode in an electrochemical cell is given below. What other half-reaction would most likely occur at the anode to produce a spontaneous reaction?
Ni^2(aq)+2e-=Ni(s)
A. Cu(s)=Cu^2+(aq)+2e-
B. Zn(s)=Zn^2+(aq)+2e-
C. Mg^2+(aq)+2e-=Mg(s)
D. Ni(s)=Ni^2+(aq)+2e-
The half-reaction is Zn → Zn⁺² + 2e⁻ which is most likely occur at the anode to produce a spontaneous reaction.
Hence, option (B) is correct answer.
What is Spontaneous Reaction ?A reaction which occurs without the intervention of outside is called Spontaneous reaction. The reaction is Spontaneous when the Δ G < 0 and [tex]E^{\circ}_{\text{cell}}[/tex] > 0.
What is Cathode and Anode ?Cathode where the reduction occurs. Anode where the oxidation take place.
Cathode: Ni⁺² + 2e⁻ → Ni
Anode: Zn → Zn⁺² + 2e⁻
______________________
Zn + Ni⁺² → Zn⁺² + Ni
The above reaction is spontaneous reaction.
Thus, from the above conclusion we can say that half-reaction is Zn → Zn⁺² + 2e⁻ which is most likely occur at the anode to produce a spontaneous reaction.
Hence, option (B) is correct answer.
Learn more about the Spontaneous reaction here: https://brainly.com/question/2855292
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Plz help..
How to name alcohols...
Answer:
Alcohols are usually named by the first procedure and are designated by an -ol suffix, as in ethanol, CH3CH2OH (note that a locator number is unnecessary on a two-carbon chain). On longer chains the location of the hydroxyl group determines chain numbering. For example: (CH3)2C=CHCH(OH)CH3 is 4-methyl-3-penten-2-ol.10
Explanation:
Answer:
ethanol formula :C2H5Oh
Which alkane is the isomer of butane called 2-methylpropane? A skeletal model of a 4-carbon chain has a straight line extending from the second and third carbons in the chain. A three-carbon chain has a straight line extending from the center carbon. A 5-carbon chain. A three-carbon chain has 2 lines extending from the same side of the center carbon.
Answer:
A three-carbon chain has a straight line extending from the center carbon.
Explanation:
Isomers are compounds having the same molecular formula but different structural formulas.
Butane and 2-methylpropane are constitutional isomers. Constitutional isomers differ in the way that the constituent atoms are connected to each other.
Butane is a straight chain compound while the compound 2-methylpropane consists of a three-carbon chain which has a straight line extending from the center carbon.
Answer:
it is b on edge 2021
Explanation:
1. A(n) bond forms when one atom gives up one or more electrons to another atom. 2. Atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are . 3. A(n) bond involves the sharing of electron pairs between atoms, also known as a molecular bond. 4. When one pair of electrons is shared between two atoms, a bond is formed. 5. When two pairs of electrons are shared between two atoms, a bond is formed. 6. A bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms. As a result, one end of the molecule has a slightly negative charge and the other a slightly positive charge.
Answer:
For 1: Ionic
For 2: Ions
For 3: Covalent
For 4: Single
For 5: Double
For 6: Polar
Explanation:
For 1:An ionic compound is formed when the complete transfer of electrons takes place from one element usually, metals (forming cation) to another element usually, non-metals (forming anions).
Hence, an ionic bond forms when one atom gives up one or more electrons to another atom
For 2:An ion is formed when an element loses or gains an electron. Two types of ions are formed which are cations and anions.
Hence, atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are ions.
For 3:A covalent bond is defined as the bond which is formed by the sharing of electrons between two atoms.
Hence, a covalent bond involves sharing electron pairs between atoms, also known as a molecular bond.
For 4:A single bond is defined as the bond in which 1 bond is present between the two atoms or 1 pair of electrons (two electrons) are shared between the atoms.
Hence, when one pair of electrons is shared between two atoms, a single bond is formed.
For 5:A double bond is defined as the bond in which 2 bonds are present between the two atoms or 2 pairs of electrons (four electrons) are shared between the atoms.
Hence, when two pairs of electrons are shared between two atoms, a double bond is formed
For 6:A polar bond is defined as the bond where unequal sharing of electrons takes place. This creates a dipole within a molecule.
Hence, a polar bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms.
PLLLLEEAASEEE HELLPP!!
What is the molarity of 150 g C6H12O6 per 0.50 L?
A. 300 mol/L
B. 75.0 mol/L
C. 1.68 mol/L
D. 0.833 mol/L
Answer: The correct option is C) 1.68 mol/L
Explanation:
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Given mass of solute}}{\text{Molar mass of solute}\times \text{Volume of solution (L)}}[/tex] .....(1)
Given values:
Given mass of [tex]C_6H_{12}O_6[/tex] = 150 g
Molar mass of [tex]C_6H_{12}O_6[/tex] = 180 g/mol
Volume of the solution = 0.50 L
Putting values in equation 1, we get:
[tex]\text{Molarity of solution}=\frac{150}{180\times 0.50}\\\\\text{Molarity of solution}=1.68M[/tex]
Hence, the correct option is C) 1.68 mol/L
Which reaction occurs at the cathode of a galvanic cell that has an aluminum electrode in an electrolyte with aluminum ions and copper electrode in an electrolyte with copper ions ? The reduction potential for the reduction of Cu^ 2+ = 0.34 The reduction potential for the reduction of AP^ 3+ =-1.68V.
Answer:
[tex]{ \bf{Cu {}^{2 + } + 2e \: → \: Cu }}[/tex]
The reaction that occurs at the cathode of a given galvanic cell is:
Cu²⁺ + 2e⁻ → Cu
What is Galvanic Cell?A galvanic cell can be defined as an electrochemical cell that converts the chemical energy of spontaneous redox reactions into electrical energy. The galvanic cell makes use of chemical reactions to generate electrical energy.
A galvanic cell consists of two half-cells and a salt bridge. Each half-cell further contains an electrode dipped into an electrolyte. When both electrodes are dipped in the same electrolyte, then there is no need for a salt bridge.
At the anode, an oxidation reaction occurs at this electrode. At the cathode, reduction occurs at this electrode. The anode has a negative potential with respect to the solution while the cathode has a positive potential with respect to the solution.
As in the question, the reduction of Cu²⁺ has a positive reduction potential. Therefore, the reduction of the copper will occur at the cathode.
Learn more about Galvanic cell, here:
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Our solar system is more than _________ in diameter.
Answer: 287.46 billion km
Explanation: calculated it myself. nah but thats the answer
What type of nuclear decay is shown by the reaction below?
A. Alpha
B. Gamma
C. Beta
O D. Fission
Answer:
C. Beta
Explanation:
Which of the following are examples of electromagnetic waves?
A.thunder, singing, tsunamis
B.sound, tsunamis, earthquakes
C.light, microwaves, radiation
Answer:
C
Explanation:
Electromagnetic waves travel at the speed of light and do not require molecules (gas, solid or liquid) to vibrate and travel.
Soundwaves when singing or from thunder vibrate particles to reach our ears and are known as mechanical waves.
Blue litmus paper is used to determine the acidity of a compound. When litmus paper detects hydrogen ions (H+), the paper turns red. Which solution will leave the blue litmus unchanged in color? hydrochloric acid (HCI) hydrobromic acid (HBr) B C sodium hydroxide (NaOH) sodium chloride salt (NaCl)
A. Hydrochloric acid (HCI)
B. Hydrobromic acid (HBr)
C. sodium hydroxide (NaOH)
D. sodium chloride (NaCI)
Answer:
Bases Do not Change the Color of Blue Litmus.
I'd go with Option C.
Sodium Hydroxide.
Iron pieces can be separated from sand using
Answer:
A Magnet or Magnetic Filtration
Answer:
Magnetic Filtration
Explanation:
That is the answer
