Is a graph that starts at 25 and drops to 21, stays the same in temperature an endothermic reaction or an exothermic reaction?
Answer:
Explanation:
Endo and Exo thermic are defined by what changes take place in the environment of the reaction.
If the temperature goes up, the reaction is giving up heat. It is Exothermic.
If the temperature goes down, the reaction requires heat. It is Endothermic.
In this case, the temperature went down. The reaction is Endothermic.
What is the volume, in liters, of 1.4 moles of CO2 gas at STP?
Answer:
22.4 L.
Explanation:
True or False: Passive transport occurs when molecules move from an area of low concentration to high concentration.
Can someone give me an example of a Hypothesis?
Answer:
if I eat more vegetables,then I will lose weight faster.
what are Metals that are less reactive than alkali metals and alkaline-earth metals called
Answer:
The first ionization energies (I1) of the alkaline earth metals are not as low as the alkali metals. The alkaline earth metals are therefore less reactive than the alkali metals (Be and Mg are the least reactive of the alkaline earth metals). Several physical properties of these elements are compared in Table 7.7.
Pls fast pls due today pls pls I don’t wanna fail
Answer:
2:true
3: true
4:false
5: true
Explanation:
Please Help
Predict the nature of the indicated covalent
bond. Polar or Non polar
Answer:
Nonpolar
Explanation:
True or False. When light passes from one medium to another the speed changes.
Answer:
Its actually true
Explanation:
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Answer:
The correct answer is "True".
Explanation:
I hope this helps!
1: How can you divide Pepper & Sand to make a solution?
Answer:
Mixture of sand, pepper powder and salt can be separated by dissolving the mixture into water. Sand and pepper powder is insoluble in water while salt is soluble. So they are separated by the filtration method.
how many neutrons of atomic mass is 31 and atomic number is 12
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
As we know, Number of protons = Atomic Number
So,
Number of protons = 12And, Atomic mass = Number of protons + Number of Neutrons (N)
therefore ~
31 = 12 + N N = 31 - 12 N = 19Number of Neutrons = 19
elements of the fourth period fill the 4s sublevel with electrons before filling the 3d sublevel. Also, some elements move an electron from a filled 4s sublevel to an unoccupied 3d sublevel. Explain these behaviors
Answer:
Elements fill the lowest energy subshells first(Aufbau's rule), and the 4s subshell is lower energy than the 3d, making the labeling deceiving. In some rare situations, the electrons would rather have Hund's rule be respected more, having all electrons facing one way with no doubled up because it is more stable(these are pretty rare and usually deal with transition metals like copper).
Hope this helps!
Explanation:
As it has less energy than the 3d orbital, the 4s orbital fills next. Following the filling of the electrons, 4s has more energy than 3d. Therefore, the two electrons in the 4s are at a higher energy than they could be in the 3d since it has a vacancy. As a result, electrons transition from a higher to a lower energy orbital.
What are electrons ?The elementary electric charge of the electron is a negative one, making it a subatomic particle. Due to their lack of components or substructure, electrons, which are part of the lepton particle family's first generation, are typically regarded to be elementary particles.
Since 4s electrons are bound by the nucleus farther away and more loosely than 3d electrons, 4s electrons are eliminated first rather than 3d electrons.
The 4s orbital should always be filled before the 3d orbitals, according to the Aufbau principle, although this isn't the case for the majority of elements. After Sc, electrons actually enter the 3d orbitals first because they have a lower energy than the 4s orbital.
Thus, electrons transition from a higher to a lower energy orbital.
To learn more about an electron, follow the link;
https://brainly.com/question/1255220
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the name of element P
Answer:
phosphorus
Explanation:
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Which type of mixture can be separated using a sieve?
A homogeneous mixture with components of varying sizes
A homogeneous mixture with components of the same size
A heterogeneous mixture with components of the same size
A heterogeneous mixture with components of varying sizes
Answer:
D: a heterogeneous mixture with components of varying sizes
Heterogeneous mixture is a combination of substances that doesn't have uniform composition and properties. Just by looking at the mixture you can differentiate the compounds because they are so different. Using a sieve, allows the components with different sizes to separate, while one is retained, the others can pass the holes in the sieve.
Explanation:
Answer: D, a heterogeneous mixture with components of varying sizes.
Heterogeneous mixture is a combination of substances that doesn't have uniform composition and properties. Just by looking at the mixture you can differentiate the compounds because they are so different. Using a sieve, allows the components with different sizes to separate, while one is retained, the others can pass the holes in the sieve.
how many moles of water in 100 grams
Answer:
There are approximately 5.55 moles
Explanation:
Rebekah finds that a solution of sugar in water has a volume of 1. 32 fl. Oz. How should she report this amount using the metric system? (1 fl. Oz. = 29. 6 mL) 0. 403 m 1. 40 qt 37. 5 g 39. 1 mL.
Rebekah reports the volume of sugar solution using metric system as 39.1 mL. Thus, option D is correct.
The metric system has been the measurement system introduced in 1790s. The system has mediated the units for the measurement of volume, mass, length.
The volume has been the space that has been occupied by matter. The volume can be denoted with SI unit L. However, the another accepted unit for volume has been mL.
Thus, the volume of sugar solution has been reported in mL.
The given sugar solution has volume of 1.32 fl. Oz
The volume in mL can be given as:
[tex]\rm 1\;fl\;Oz=29.6\;mL\\1.32\;fl\;Oz=1.32\;\times\;29.6\;mL\\1.32\;fl\;Oz=39.1\;mL[/tex]
The volume of the sugar solution reported by Rebekah on the metric scale has been 39.1 mL. Thus, option D is correct.
For more information about the metric system, refer to the link:
https://brainly.com/question/25011390
A gas occupies 900 mL at a temperature of 27 °C. What is the volume at
132 °C?
Answer:
4400 ml
Explanation:
Name the following molecule in the image
[tex]\\ \sf{:}\longrightarrow 2,4-diethyl-2-methylpentane[/tex]
Hello! Everyone:) I was just wondering if you can help me with my test.
Points: 99
Answer:
By their properties ;)
Explanation:
[tex]\Large \boxed{\sf by \ their \ properties}[/tex]
Every element has a set of particular characteristics. Each has a unique atomic and mass number because they contain a different ratio of protons and neutrons. The number of protons in an element mirrors the element's atomic number. The mass number equals the sum of the element's protons and neutrons.
According to increasing atomic numbers, chemical elements get organized. Periods and groups are the names of the horizontal rows and vertical columns, respectively. The chemical characteristics of elements within the same group are comparable due to their similar valency and number of outer electrons.
A chemist heats a gas within a sealed, rigid container. Which statement describes the changes that occur in the gas? (1 point)
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure
increases
-The gas particles move slower and hit the sides of the container with less force, consequently, the pressure decreases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
increases
-The gas particles move faster and hit the sides of the container with more force, consequently, the pressure
decreases
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
An increase in the temperature of a gas increases the collision rate of the molecules of the gas according to the kinetic theory.
With increased kinetic energy, the molecules of the gases collide more frequently with each other and the walls of the container.
The collision creates an increase in the magnitude of pressure inside the container.
More on the kinetic theory of gases can be found here: https://brainly.com/question/15354399?referrer=searchResults
Answer:
C
Explanation:
When a gas is heated in a sealed container, the gas particles move faster and hit the sides of the container with more force leading to an increase in the pressure of the gas.
Which of the following is a binary compound?
What is formed if two or more atoms join together?
A. Compound
B. Electronegativity
C. Nucleus
D. Element
HELP
Answer:
compound
Explanation:
compound = A substance consisting of atoms or ions of two or more different elements in definite proportions joined by chemical bonds into a molecule.
What did you observe about the properties of the sodium carbonate mixture before the substances were mixed together?
Answer:
Would you consider adding a sodium carbonate solution to a magnesium sulfate .
Explanation:
??
Help answer these chemistry questions
Answer:
45th answer is pure and properties 42 is periodictable
Mr. Jenson's class is observing the growth of one kind of pea plant.
The class wants to design an experiment to answer the question, "What amount of water will cause the plants to produce the greatest number of peas?"
What could the class do to create the experiment?
A.
give all the pea plants the same amount of water and count the number of peas that the plants produce
B.
give all the pea plants different amounts of water and only guess the number of peas that the plants produce
C.
give all of the pea plants different amounts of water and count the number of peas that the plants produce
D.
stop watering all of the pea plants and then count the number of peas that the plants produce
Answer:
The answer would be C. Giving the pea plants a different amount of water in each one can help you observe how much water produces the most peas in a pea pod.
The answer is C to give all of the pea plants different amounts of water and count the number of peas that the plants produce
Explanation:
Answer:
C. give all of the pea plants different amounts of water and count the number of peas that the plants produce
Explanation:
The class wants to design an experiment that answers the question, "What amount of water will cause the plants to produce the greatest number of peas?"
To answer the question, the experiment should show how many peas the plants produce when they are given different amounts of water. The best way to do this would be to give all of the plants different amounts of water and count the number of peas that the plants produce.
What are the most important topics for revision in chemistry?
Answer:
structure of atom
states of matter
classification of elements and periodicity in properties
thermody namic
Equilibrium
Redox reacation
A 0.03 mol sample of NH4NO3 (s) is placed in a 1 L evacuated flask, which is then sealed and heated. The NH4NO3 (s) decomposes completely according to the balanced equation above. The total pressure in the flask measured at 400 K is closest to which of the following? (The value of the gas constant, R, is 0.082 L atm mol-1 K-1.)
a. 3 atm
b. 1 atm
c. 0.5 atm
d. 0.1 atm
e. 0.03 atm
The total pressure in the flask measured at 400 K is 1 atm
The correct answer to the question is Option B. 1 atm
From the question given above, the following data were obtained:
Number of mole (n) = 0.03 mole Volume (V) = 1 L Temperature (T) = 400 KGas constant (R) = 0.082 atm.L/Kmol Pressure (P) =?Using the ideal gas equation, we can obtain the pressure in the flask as follow:
PV = nRT
P × 1 = 0.03 × 0.082 × 400
P = 1 atmTherefore, the total pressure in the flask measured at 400 K is 1 atm
Learn more on ideal gas equation: https://brainly.com/question/4147359
Answer: a: 3 atm
Explanation:
0.03 mol NH4NO3 decomposes into 0.09 mol of gas total, thus we multiply 0.09 by 0.082 and 400K to get our answer of about 3 atm.
Using the “rule of 8” explain why carbon is the backbone of organic molecules
Answer:
Carbon has 4 valence electrons (electrons that are used in bonding), and therefore it can make 4 bonds which is the most one can (other than some exceptions, but in general it is the most). It wants to make 4 bonds so it can reach a full octet of 8 elections, hence the rule of 8.
Explanation:
Answer:
I suggest you See Explanation. But tldr: Carbon forms four bonds with no lone pairs.
Explanation:
By "rule of 8" I am assuming you mean "Octet Rule." In case you don't know, the octet rule (or rule of 8) is a rule referring to the maximum number of valence shell electrons that an atom can hold: 8 electrons. However, there are exceptions to this: octet-deficient and expanded octet atoms. Octet-deficient atoms follow what is known as the duet rule (or rule of 2), as seen in the case of H and He, or have have a capacity of up to 6 electrons in their valence shell, as seen in the case of B and Be. Expanded octets contain 10, 12, or even 14 electrons and occur in Period 3 elements and after. (It was previously assumed that this was due to d-orbital hybridization but that hypothesis has been disproven and currently an explanation regarding expanded octets doesn't exist. Yet another Nobel Prize worthy concept to solve when you have free time!)
Anyways, how does this all apply to Carbon being the backbone of the millions of organic molecules? Well, carbon follows the octect rule. Unlike duet rule atoms, it is not limited to one bond with another atom. Neither does it hold many lone pairs to itself nor form over four bonds at once causing a decrease in stability. No, Carbon forms four bonds with no lone pairs and has perfect stability in terms of both formal charge and octect rule in many of its structures. Its capacity to bond to up to 4 atoms without comprimising stability is the reason why carbon is the backbone of organic molecules. If you feel this answer helped, gimme brainliest, have a great day! :)
The bacteria are known to be prokaryotes. Prokaryote means
A
organisms whose cells have no nucleus
B
organisms who are made of many cells
C
organisms who make their own food
D
organisms whose cells have a nucleus
Answer:
prokaryote, also spelled procaryote, any organism that lacks a distinct nucleus and other organelles due to the absence of internal membranes. ... Bacteria are among the best-known prokaryotic organisms. The lack of internal membranes in prokaryotes distinguishes them from eukaryotes.
Explanation:
Which of these substances is commonly refined by electrolysis?
brine
rust
titanium
water
I believe the answer would be titanium. Good luck on your assignment and have a happy christmas :)
how do I know which substance is being reduced?