Answer:
1. Combine iron and copper (II) sulfate solution. (Hint: Iron will form the iron (III) ion)
Fe + CuSO4 → FeSO4 + Cu
2. Combine lead (II) nitrate and potassium iodide solutions.
Pb(NO3)2+ Kl → Pbl2 + 2KNO3
3. Combine magnesium metal and hydrochloric acid solution.
Mg + HCl → MgCl2 + H2
4. Electrolysis (splitting) of water.
H2O → 2H2 + O2
5. Burning magnesium.
Mg + O2 → Mg2+O2-
Explanation:
A sixth grade teacher takes students on a field trip to the beach. One student finds several pebbles that have a rounded shape and are smooth to the touch. What process most likely shaped these pebbles?
Answer:
C: The shape of the pebbles is a result of weathering and deposition
Explanation:
For the several pebbles to have a rounded shape and smooth to the touch, it will undergo weathering and deposition. This is because weathering involves breaking down of rocks and creating new sediments. This weathering could be either chemical weathering or physical weathering where Chemical weathering is the decomposition of rocks which are caused by chemical reactions and which result in formation of new compound while physical weathering is the breakdown of rocks into smaller pieces. On the other hand, deposition occurs when the agents of erosion such as wind or water deposit sediments from one spot to another which in turn changes the shape of the land.
Thus, the shape of the pebbles are as a result weathering of the parent rocks and from deposition.
Which of the following statements is true regarding scientific hypotheses?
A.Every hypothesis is valuable, whether or not it is testable.
B.A testable hypothesis is valuable, even if evidence shows that it is false.
C. A testable hypothesis is valuable only if all evidence supports it. D. There are no valuable hypotheses.
At what temperature, would the volume of a gas
to be doubled. If pressure at the same time increases
from 700 to 800mm, the gas being at
initially
at 0°C
Explanation:
P1V1 = nRT1
P2V2 = nRT2
Divide one by the other:
P1V1/P2V2 = nRT1/nRT2
From which:
P1V1/P2V2 = T1/T2
(Or P1V1 = P2V2 under isothermal conditions)
Inverting and isolating T2 (final temp)
(P2V2/P1V1)T1 = T2 (Temp in K).
Now P1/P2 = 1
V1/V2 = 1/2
T1 = 273 K, the initial temp.
Therefore, inserting these values into above:
2 x 273 K = T2 = 546 K, or 273 C.
Thus, increasing the temperature to 273 C from 0C doubles its volume, assuming ideal gas behaviour. This result could have been inferred from the fact that the the volume vs temperature line above the boiling temperature of the gas would theoretically have passed through the origin (0 K) which means that a doubling of temperature at any temperature above the bp of the gas, doubles the volume.
From the ideal gas equation:
V = nRT/P or at constant pressure:
V = kT where the constant k = nR/P. Therefore, theoretically, at 0 K the volume is zero. Of course, in practice that would not happen since a very small percentage of the volume would be taken up by the solidified gas.
Suggest two reasons why the mass deposited was different from the expected value
VERY URGENT PLZ HELP!!!
Answer:
1) Dissolution of the copper anode
2) Time of the reaction
Explanation:
The figure shows the electrolysis of Copper Chloride using copper electrodes.
In aqueous solution, the ions present in the solution include: H⁺, OH⁻. Cu²⁺ Cl⁻
The half equations for the reaction are:
At rhe Anode (positive electrode) : 2Cl⁻(aq) - 2e = Cl₂(g)
At the Cathode (negative electrode) Cu²⁺ (aq) + 2e = Cu (s)
Hence copper ions are reduced at the cathode by gaining two electrons to form copper solid deposits. It is the mass of the deposited copper that the student measured over time.
Reasons why the actual mass is different from the expected mass
1) Dissolution of the copper Anode: The electrodes used for this experiment are copper electrodes as both the positive and negative electrode.
Under the influence of an electric current, the copper anode will dissolve by gaining electrons and go into solution as copper II ions (Cu²⁺). thereby increasing the amount of copper ions in solution.
The aqueous copper ions from the anode and from the copper chloride (CuCl₂ (aq) electrolyte will migrate to the negative cathode, gain electrons, and get deposited as pure copper solid. This increases the mass of copper solid deposited at the cathode.
2) Time: As the time of the reaction from zero to sixty (60) minutes under the influence of an electric current, more of the copper anode will dissolve, migrate to the cathode and get deposited as copper solid.
Hence as the time of the reaction increases, more of the copper ions will be deposited as copper solid thereby increasing the value of the actual mass of copper deposited.
Dissolving of copper and time are the two reasons for the different value to the expected value.
Dissolution of copper and less time are the two reasons for the different form the expected value because during the accumulation of copper on the anode some amount dissolved in the solution and not accumulated at the anode while on the other hand, time is also a factors which gives us different value as compared to expected value.
60 minutes are less time for the deposition of copper at the anode so if the time is extended then the value is same or near to the expected value so we can conclude that dissolving of copper and time are the two reasons for the different value to the expected value.
Learn more: https://brainly.com/question/19246633
An unknown substance has a density of 56 g/cm3. Its volume is 3.5 cm.
What is the mass of this unknown substance?
Answer:
The answer is 196 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volume
From the question we have
mass = 56 × 3.5
We have the final answer as
196 gHope this helps you
Consider the balanced equation:
3Mg(OH)2 + 2H3PO4 Mg3(PO4)2 + 6H20
If you have 3 moles of Mg(OH)2, how many moles of water will be produced?
A
2
B
3
6
D
1
Answer:
A). 3 Mg, 2 P, 14 O, 12 H
Explanation:
write the electron configurations for the elements that are identified only by these numbers
a. 15 b. 12 c. 9 d. 18
atomic number 15
1S^2,2S^2,2P^6,3S^2,3P^3
atomic number 12
1S^2,2S^2,2P^6,3S^2
atomic number 9
1S^2,2S^2,2P^5
atomic number 18
1S^2,2S^2,2P^6,3S^2,3P^6
!!please help asap ty!!
2. How many atoms of zinc are present in 0.48 mol of zinc?
(show solution)
Answer:
2.89× 10²³ atom
Explanation:
Given data:
Number of atoms of Zn = ?
Number of moles of Zn = 0.48 mol
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atom
0.48 mol × 6.022 × 10²³ atom / 1mol
2.89× 10²³ atom
what is the measure of the amount of matter in a given amount of space
Answer:
volume
Explanation:
it is always measured in volume
Can someone help me please ?
Answer:
the second one that is it
Explanation:
bc i am o smaart like tht
Please help click the picture
Answer
D
Explanation:
The formula is going to be Products / Reactants.
That means only B and D can be correct. The balance numbers to the equation are the powers which means that the answer is D
Choose all the answers that apply.
Which of the following best describes the movement of the objects in this ticker tape diagram? (Check photo added)
Object B has more velocity than object C.
Object C has more velocity than object B.
Object A is accelerating.
Object B is decelerating.
Object C has a constant velocity.
Answer:
2, 4, and 5
Explanation:
have a nice day:)
Answer:
2, 4, and 5
Explanation:
Hope this Helps!!!
please give me Brainlest
How many Na and Cl molucules are in this atom? Please help
Answer: Check my answers.
Explanation:
There are four classes of macromolecules (polysaccharides or carbohydrates, triglycerides or lipids, polypeptides or proteins, and nucleic acids such as DNA & RNA). Carbohydrates and lipids are made of only carbon, hydrogen, and oxygen (CHO). Proteins are made of carbon, hydrogen, oxygen, and nitrogen (CHON).
How does the law conservation of matter apply to machines
7. Which of the following properties identifies a pure substance?
A. soluble in water
B. tasteless and odorless
C. has a constant boiling temperature
D. can be changed from liquid to gas and back to liquid.
Answer:
Soluble in water
Explanation:
If a gas in a closed container is pressurized from 15.0 atmospheres to 16.0
atmospheres and its original temperature was 298 degrees Kelvin, what
would the final temperature of the gas be?
Answer:
T₂ = 317.87 K
Explanation:
Given data:
Initial pressure = 15 atm
Final pressure = 16 atm
Initial temperature = 298 K
Final temperature = ?
Solution:
According to Gay-Lussac Law,
The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.
Mathematical relationship:
P₁/T₁ = P₂/T₂
Now we will put the values in formula:
15 atm / 298K = 16 atm/T₂
T₂ = 16atm × 298 K / 15 atm
T₂ = 4768 atm. K / 15 atm
T₂ = 317.87 K
3. Why does a marshmallow burn over an open fire, but not in a microwave?
because there is not fire in the microwave
explain how do the octect forms in cations and anions
Answer:
Explanation:
-Octet forms when the valence electrons are gained, lost or shared.
-In order to become stable, which has 8 valence electrons (octet), nonmetal groups such as group 17, needs to gain 1 more electron to become 8/ octet.
When gaining that 1 electron, group 17 elements become negative ion or anions
-For metal groups such as group 1, they need to lose that 1 electron to become stable. When they lose that 1 electron, they become positive ion which is cation.
Hope this helps
A substance is called malleable
Answer: Malleability is a substance's ability to deform under pressure (compressive stress). If malleable, a material may be flattened into thin sheets by hammering or rolling. Malleable materials can be flattened into metal leaf. Examples of malleable metals are gold, iron, aluminum, copper, silver, and lead.
Explanation: This what you needed?
Answer:
Malleability is a substance's ability to deform under pressure (compressive stress). Examples of malleable metals are gold, iron, aluminum, copper, silver, and lead. Gold and silver are highly malleable. When a piece of hot iron is hammered it takes the shape of a sheet.
what does c3h8 equal
When natural resources combine during a chemical reaction they create
A second unknown substance has a density of 80 g/cm and a mass of 570g. What is the volume?
Answer:
25 g
10 cm
3
=
2.5 g/cm
3
Explanation:
Based on the wintertime La Niña weather map, what do you think Florida's temperature and precipitation would be like during a winter El Niño event?
*Hurry!!!!!!!! 55 points!!*
Answer:
Temperature decreases and precipitation increases.
Explanation:
Temperature of Florida decreases and precipitation increases during a winter El Niño event. Due to El Niño event, precipitation occurs above average in Florida during Fall-Winter-Spring season. Storminess also increases during this El Niño event which increases the threat of severe weather in Florida during El Niño winters.
Answer: when Pacific waters cool, moving the tropical thunderstorms so that the wind shear in the Atlantic wanes during hurricane season
What might happen if you mixed a strong acid with an equally strong base?
Question 4 options:
You would wind up with a pH neutral salt and water
The base would destroy the acid.
You would see an explosive chemical reaction.
The acid would destroy the base.
Answer:
You would wind up with a pH neutral salt and water
Explanation:
When they are equally strong they will both neutralize each other, and the acidic and basic properties are no longer there.
Describe the three main concepts that make up cell theory.
Answer:
Answers are numbered below:
Explanation:
"The three parts of the cell theory are as follows: (1) All living things are made up of cells, (2) Cells are the smallest units (or most basic building blocks) of life, and (3) All cells come from preexisting cells through the process of cell division..."
I hope this helps you! Have a great day!
How does pulse change with exercise?
Answer:
Your muscles require extra oxygen when you workout, about three times as much as the resting muscles. This need implies that the heart begins to pump harder, which allows for a faster pulse. Your lungs, meanwhile, draw in more oxygen as well, hence the harder breathing.
Explanation:
when you exercise, your heart starts pumping blood faster, which eventually makes your pulse faster.
if 10 ml of acetone (60) is diluted with water to a total solution volume of 200 ml, what is the percent by volume of acetone in the solution?
Answer:
5%
Explanation:
Given parameters:
Volume of original acetone before dilution = 10ml
Volume of diluted solution = 200ml
Unknown:
Percent volume of acetone in the solution = ?
Solution:
To find the percent volume of acetone in the diluted solution, use the expression below;
Percent volume of acetone = [tex]\frac{volume of original acetone}{diluted volume} x 100[/tex]
Insert the parameters and solve;
Percent volume of acetone = [tex]\frac{10}{200}[/tex] x 100 = 5%
Magnesium chloride is a salt formed from ionic bonding between one magnesium atom and two chlorine atoms. A magnesium atom has two electrons in its outer (third) shell; chlorine atoms have seven electrons in their outer shell. How many electrons would be in the outer shell of the magnesium once it becomes an ion
Answer:
Outermost shell of magnesium ion has 8 electrons.
Explanation:
Mg + Cl → MgCl2
Mg electronic configuration = [tex]1s^22s^22p^63s^2[/tex]
Cl electronic configuration = [tex]1s^22s^22p^63s^23p^5[/tex]
In the third shell there are two electrons while in Chlorine there are 7 electrons.
The ions formed will be Mg^+2 and Cl-
Since Magnesium has donated 2 electrons to form Mg^+2 ion now the its ionic electronic configuration becomes
Mg^+2 = [tex]1s^22s^22p^6[/tex] ( 2 , 8)
Therefore the outermost shell of magnesium ion has 8 electrons.
What reaction would the chemical equation 2H2O→2H2+O2 represent?
combustion of water
decomposition of water
replacement of water
formation of water
Answer:
decomposition of water
Explanation:
The reaction will represent the decomposition of water. It usually carried by an electrolytic process in the laboratory.
Water molecule is broken down into its constituent hydrogen gas and oxygen gas components. The breaking down of one compound to give other compounds is decomposition. This is not a replacement reaction. In decomposition, we often start with a single reactant and results in one or more products.Answer:
decomposition of water
Explanation:
i took the quiz and it was right
El agua oxigenada es una disolucion al 7% en volumen de peroxido de hidrogeno en agua , que se usa para destruir microorganismos en heridas leves y asi de reducir la posibilidad de infeccion en los tejidos. El volumen de peroxido de hidrogeno nesesario para preparar un litro en disolucion al 6% en volumen es:
Answer:
857mL de la solución al 7%
Explanation:
Una solución de agua oxigenada (H₂O₂) al 7% contiene 7mL de peróxido de hidrógeno por cada 100mL de solución = 7mL H₂O₂ / 100mL Sln
Para preparar un litro = 1000mL de disolución al 6% de peróxido de hidrógeno se requieren:
1000mL Sln * (6mL H₂O₂ / 100mL Sln) = 60mL H₂O₂
Para obtener 60mL de H₂O₂ a partir de la solución al 6% se requieren:
60mL H₂O₂ * (100mL Sln / 7mL H₂O₂) =
857mL de la solución al 7%