Answer:
Hi there
Thermal Energy and Chemical Reactions
The device controlled the activation as shown by the water holding room temperature for 15 seconds until activation by crushing the pills. The temperature rose 30° over two minutes,showing a measurable exothermic reaction from the Calcium Chloride dissolving in the water.
Pour 5mL water in a quart bag
Place Thermometer in the bag to make contact
Fill two gelatin 000 capsules with 1 gram of Calcium Chloride
Place capsules into the bag
Wait 15 seconds to crush the capsules while they are submerged in the water
-Temperature
0 seconds 75 degrees
15 seconds - Activation 75 degrees
30 seconds 85 degrees
60 seconds 95 degrees
90 seconds 104 degrees
120 seconds 105 degrees
Conclusion: During a reaction, thermal energy from the environment is converted into chemical energy stored in the products.
Brainliest plz
Can someone answer that first this pls im lost
How much aluminum can be extracted from 3.5 metric tons of bauxite ore which is 70% aluminum oxide?
Answer:
A) 17.5%
B) 1) 2135 kg
2) 375 kg
C) 91.8
Explanation:
Part (A):
1 tonne= 1000 kg= 100%
Aluminium oxide= 825 kg= 82.5%
Iron (lll) oxide= 100 kg= 10%
Sand= 85 kg= 7.5%
That makes total of 100%
So, the percentage of impurities= Iron (lll) oxide + Sand
=> 10 + 7.5= 17.5%
Part (B):
(1) 1 tonne= 427 kg
Multiplying both sides by 5
=> 5 tonne= 427 * 5
=> 5 tonne = 2135 kg
(2) 1 tonne contains 75 kg sand as impurity
=> 1 tonne= 75 kg
Multiplying both sides by 5
=> 5 tonnes = 75 * 5
=> 5 tonnes = 375 kg
Part (C):
If all of the iron oxide was removed, then only aluminium and sand are left.
Aluminium = 825 kg
Sand= 74 kg
Total of them makes it:
=> 825 + 74 = 899
So,
% age of Aluminium= 825/899 * 100
% age of Aluminium= 0.918 * 100%
% age of Aluminium= 91.8%
in a battery that uses a licoo2 cathode approximately 50% of the lithium migrates from the cathode to the anode on charging. in a battery that uses a limn2o4 cathode what fraction of the lithium in limn2o4 would need to migrate out of the cathode to deliver the same amount of lithium to the graphite anode?
Answer:
92.4%
Explanation:
Assume 100g of the cathode material. The LiCoO2 cathode has 7.09 g of Li. If half of Li migrates during charging, 3.55g Li migrates. 100g of the LiMn2O4 cathode contain 3.84g of Li. The fraction of lithium in LiMn2O4 that would need to migrate out of the cathode to deliver the same amount of lithium to the graphite anode:
(3.55g/ 3.84g ) * 100% = 92.4%
From electrolysis, 92.4% would need to migrate out of the cathode to deliver the same amount of lithium to the graphite anode.
What is electrolysis?
Electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell. The voltage that is needed for electrolysis to occur is called the decomposition potential.
Assume 100 g of the cathode material. The LiCoO₂ cathode has 7.09 g of Li. If half of Li migrates during charging, 3.55 g Li migrates. 100 g of the LiMn₂O₄cathode contain 3.84 g of Li. The fraction of lithium in LiMn₂O₄ that would need to migrate out of the cathode to deliver the same amount of lithium to the graphite anode:(3.55 g/ 3.84 g ) × 100% = 92.4%
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how long does it take cream cheese to get to room temperature?
Since cream cheese has such a high fat content, it doesn't take long to come to room temperature if the room is relatively warm. It takes about thirty minutes on the counter to soften significantly, and about an hour to fully come to room temperature again, depending on the temperature outside and in your kitchen
Determine the rate of reaction at 50 C when the loss of mass is 0.95 g. Show your working. Give your answer to 2 significant figures.
* 20 points for who gets it *
This problem is providing information about the loss of mass for a reaction 50 °C as a function of the time elapse. Thus, when taking a look at the given graph, we can trace a horizontal line on the y-axis at 0.95 g in order to intercept it with the curve, and hence, figure out the time at which that loss of mass takes place.
Thus, we can see that when the loss of mass hits 0.95 g, the corresponding time on the graph is about 80 seconds, and hence, the rate of reaction turns out to be:
[tex]r=\frac{0.95g}{80s}\\\\r=0.012\frac{g}{s}[/tex]
Which has two significant figures as required.
Learn more:
https://brainly.com/question/24072508 https://brainly.com/question/8983899Magnesium has three naturally occurring stable isotopes, 24Mg (abundance 78.99%), 25Mg (abundance 10.00%) and 26Mg (abundance 11.01 %). Calculate the relative atomic mass of magnesium, giving your answer to 2 decimal places.(2)
Explanation:
M = molar mass
p= percentage abundance
[tex]rel.atm.mass = \frac{ M1p1 + M2p2 + M3p3}{100} \\ r.a.m = \frac{24 \times 78.99 + 25 \times 10 + 26 \times 11.01}{100} \\ r.a.m = \frac{1895.76 + 250 + 286.26}{100} \\ = \frac{2432.02}{100} \\ 24.32[/tex]
BRAINLIST
are most of the elements on the periodic table classified as a metal or a non-metal?
Answer:
Metals
Explanation:
There are more metals next time trying checking the table they will be in colored squares to count to see which has more! HOPE THIS HELPED!
<3 :D
what is the differece between substance and matter?
Answer:
Anything that occupies space and has mass is matter but the matter that has specific composition and chemical characteristics is substance
Answer:
Substance: Something that has only 1 atom, for example; Water.
Matter: Made up of more than 1 atom, example; Humans
Explanation:
As said a substance is something that has only 1 atom like water or tin.
Matter is well almost everything in the universe, there's a reason some people say; This is Human Matter. I'm pretty sure it's somewhere in the bible too.
If you were to search it up the other persons answer would come up
why does it make sense for the valence electrons to increase going across a period?
What is collision theory?
A.a theory stating that reactants must collide with products in order for a chemical reaction to occur
B.a theory stating that there must be minimal kinetic energy between products for a chemical reaction to occur
C.a theory stating that a chemical reaction occurs only when reactants strike each other at the correct orientation and with sufficient kinetic energy
D.a theory stating that a chemical reaction occurs only when reactants are placed in separate containers and the containers are then placed close together
Answer:
A
Explanation:
collision theory is a theory used to predict the rates of chemical reactions, particularly for gases. The collision theory is based on the assumption that for a reaction to occur it is necessary for the reacting species (atoms or molecules) to come together or collide with one another
HELP!!!! I need help with number 11 and 12
Answer:
V1/n1 = V2 /n2
0.236/0.306 = V2/ 4.40
V2 = 3.39 L
In an ionic compound, the total positive charge of all the positive ions ____ the total negative charge of all the negative ions.
Answer:
I think it would be 0 since cations and anions must always combine in such a way so that their charges cancel.
BRAINLIEST TO CORRECT ANSWER
Answer:
A right? I'm pretty sure it's A
Select the atom that will attract the electron pair (:) more strongly (the atom with the greater electronegativity)
HELP PLEASE
what is the answer to this:magnesium+oxygen
Answer:
magnesium oxide
Explanation:
what are valence electrons? why are they so important in chemistry?
Answer:
Valence electrons are negatively charged particles located in the outermost shell of atoms that can be transferred or shared with other atoms. Valence electrons are important in chemistry because the number of valence electrons in a particular atom can be used to determine how the atom will react chemically with other atoms.
The gain of electrons by an element or ion in a reaction is called __.
A. fractionation
B. Disproportionation
C. Oxidation
D. Reducing
Answer:
Reduction
Explanation:
took the test
2. Some water returns to the air from lakes and the oceans. This process is called: A. Evaporation B. Condensation C. Groundwater
Answer:
A. evaporation
Explanation:
Answer:
This process is called (A) evaporation.
Evaporation is the process is where water turns into a vapor or air.I hope this helped at all.
At what point on a heating curve graph does a phase change occur?
at each plateau
at the first plateau
at each slope
at the last slope
Answer:
Electrical Bonding Investigation Data Quick Check
Explanation:
B. Heat energy is added to the substance, weakening the electrica attraction between molecules.
C. Both the melting point and boiling point are lower
C. The lone pairs of electrons in the oxygen atom causes the molecule to be bent; the oxygen atom has a particle negative charge, while the hydrogen atom have particle positive charges
D. Phase change
C. At each plateau
¿que otro nombre reciben las órbitas?
I need help with the question below
Answer:
the answer is Crystal structures
Is the charge of anucleus positive, negative or neutral what about the charge of an atom
Answer:
The nucleus has an overall positive charge as it contains the protons.
Explanation:
Every atom has no overall charge (neutral). This is because they contain equal numbers of positive protons and negative electrons. These opposite charges cancel each other out making the atom neutral.
b) How much Phosphorus Pentachloride can be made if you begin with 17.8 g of chlorine gas?
How many total atoms of Nitrogen are shown in the formula below?
4N₂O
2
4
6
8
Answer:
8
EXPLANATION hope this helps you
Answer:8
Explanation:
explain why heating a solution increases the solubility of a solute
[tex] \: \: \: \: \: [/tex]
The addition of more heat facilitates the dissolving reaction by providing energy to break bonds in the solid. This is the most common situation where an increase in temperature produces an increase in solubility for solids.hope it helps[tex] \: \: \: \: \: \: [/tex]
In the image above, the region labeled “ A “ is called the . . .
White matter
Dorsal Horn
Central Canal
Ventral Root
Answer:
Ans B)=====> Dorsal Horn
Two arms, each known as a Dorsal Horn, are formed by the core grey matter at the back of the spinal cord. In the image, the region labeled “ A “ is called the Dorsal Horn. Therefore, option B is correct.
What is dorsal horn ?One of the gray longitudinal columns discovered inside the spinal cord is the dorsal horn. Through the dorsal roots of the spinal nerves, it predominantly serves as the end of primary afferent fibers.
A complex network of excitatory and inhibitory interneurons, as well as projection neurons, make up the dorsal horn, which serves as an intermediary processing center for this information. It transmits the processed somatosensory information from the spinal cord to the brain.
The cell bodies of sensory neurons are located in the dorsal horns. The ventral horns are two arms of central grey matter that are found at the front of the spinal cord.
Thus, option B is correct.
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why are there no elementary substances that have the ionic bond?
This problem is asking for the reason behind the nonexistence of elementary substances with ionic bonds. First of all, it is necessary to bear to mind that the definition of the type of bond in a compound depends on the difference electronegativity that is present between two of the atoms composing it.
For instance, in binary salts, such as KCl, NaCl, KBr and so on, we are able to know these are all ionic because they are composed by a metal and a nonmetal, which have the smallest and largest electronegativities, so that the difference electronegativity is large enough to produce an ionic bond.
In contrast, elementary susbtances, such as liquid bromine (Br2) and gases such as H2, N2, Cl2, F2 and O2, since they are all nonmetals and the same type, the electronegativity difference will be 0 and therefore, they will not be ionic but covalent.
Learn more:
https://brainly.com/question/15105831https://brainly.com/question/14509196During ionization, metals lose electron, this change is called?
Ans
This is called oxidation
Explanation:
the oxidation number of a metal ion is more than the oxidation number of metal atom
Which three things does a plant need to create a glucose molecule in photosynthesis?
Choose all correct answers.
water
oxygen
carbon dioxide
sunlight
How does calculating the kinetic energy of an object at different velocities help understand the relationship between kinetic energy and velocity?
Answer:
Kinetic energy depends on the velocity of the object squared
Explanation:
Kinetic energy depends on the velocity of the object squared. This means that when the velocity of an object doubles, its kinetic energy quadruples. ... Kinetic energy must always be either zero or a positive value. While velocity can have a positive or negative value, velocity squared is always positive.