An ice cube melts in the hot sun. Is this exothermic or endothermic and
why?
Answer:
Endothermic
Explanation:
In order to melt the ice cube, heat is required, so the process is endothermic. Endothermic reaction In an endothermic reaction, the products are higher in energy than the reactants. Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings by the reaction.
which type of rection has the general formuial ab+cd
What is the Atomic number of 12
Answer:
atomic number of 12 is MG
Explanation:
Magnesium
7th grade help me plzzzzz
Answer:
A & B
Explanation:
The answer for the first one is A because the proton is found in the nucleus with the neutron
The answer for the second was is B because the Neutrons, protons and electrons are all subatomic particles, as they are the main particles that make up an atom.
Proton = Positive Charge (+)
Neutron = Neutral charge (=)
Electron = Negative Charge (-)
Answer:
1- positive
2- A
3-A
Explanation:
all energy travels in waves true or false
If the hydronium ion concentration of a substance is 1.0 X 10-6 M, what would be the pH of that substance??
Show/Describe your work.
Why do gases diffuse more quickly than liquids?
Choose the correct answer.
A) Liquids can be compressed easily.
B)The particles in gases are not mobile.
C)Liquids are always at lower temperatures than gases.
D)Gas particles move rapidly and have space between them.
Answer:
D)Gas particles move rapidly and have space between them.
Explanation:
Matter exists in three states namely: solids, liquids and gases. The particles contained in these three states are different from one another. In the gaseous state, the particles are FAR APART from one another i.e. space exists and they move at a very fast rate in contrast to the particles of a liquid, which have less space and move slower.
This rapid movement of gas particles within a less restricted space accounts for the reason why gaseous substances DIFFUSE more quickly than liquids.
A binary molecule consists of how many atoms?
O1
02
3
4
Answer:
2
Explanation:
BIonary bi means 2
i hope this helps :)
Which method of heat transfer allows you to fry an egg in a frying pan on the stove?
Answer:
Conduction
Explanation:
Answer:
Conduction is correct
Explanation:
what is salt
explinnn hhhhhh hh hh
Answer:
salt is a very well known seasoning
Explanation:
hope this helped :)
every spring has an equilibrium position which statement describe a spring at it equilibruim position?
What is the name of the process that is used to clean up environmental waste and how does it work?
Answer:
Environmental cleanup includes removal of heavy metals and other toxic contaminants from the environment and the process is called remediation.
Two moles of acetyl chloride was mixed with two moles of dimethylamine. After the reaction is complete, what species can be found in the mixture
Answer:
See explanation
Explanation:
The reaction is shown in the image attached. This reaction occurs by a carbocation (ionic) mechanism.
The lone pair on the nitrogen atom attacks the carbocation leading to the formation of the product as shown in the image attached.
Since the reaction occurs in a 1:1 ratio, two moles of reactants yields two moles of product.
i will give the first person brainliest! please helppp
okay so the Answer is c
Which of the following conclusions about the two intermolecular forces is correct? X represents London dispersion forces, and Y represents ion-dipole forces. X represents dipole-dipole forces, and Y represents ion-dipole forces. X represents hydrogen bonding, and Y represents dipole-dipole forces. X represents London dispersion forces, and Y represents dipole-dipole forces.
Answer:
X represents London dispersion forces, and Y represents dipole-dipole forces.
Explanation:
1 point
Which element requires the least amount of energy to remove its valence electron(s)?
barium
chlorine
oxygen
carbon
PLEASE HELP!! Circuit A consist of two wires and a battery. Circuit B consist of the same strength battery and the same type of wires, but it also contains a light bulb. Which circuit has more resistance?
Answer:
light bulb B
Explanation:
more resistance
Answer the question below
Answer:
C
Explanation: I think
Whenever the same two elements form more than one
compound, the different masses of one element that combine
with the same mass of the other element are in the ratio of
small whole numbers.
TRUE
FALSE
Answer:
The answer is true
Explanation: Because The law of multiple proportions states that when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers.
Short Answer Questions 18 points
1) What year was Mendeleev born? _______________________________________
2) Where was Mendeleev born? ______________________________________
3) Explain how Mendeleev arranged his periodic table.______________________________________
4) What were the 3 Elements that were missing from Mendeleev’s Periodic Table?
__________________________________________________________________
5) When did Mendeleev die? Exact date ____________________________________
6)Which particles are in the nucleus of an atom? ______________________________
1) He was born on February 8, 1834
2) He was born in Tobolsk, Russia
3) Mendeleev arranged the elements in order of increasing relative atomic mass.
4) Gallium, germanium, and scandium
5) He died on February 2, 1907
6) Protons (positive charge) and neutrons (neutral charge)
Question in picture!!!!!!
Answer:
6 atoms
Explanation:
1. With the aid of a Hess cycle, determine the enthalpy of the decomposition reaction of sodium nitrate, NaNO3 to sodium nitrite, NaNO2 and oxygen, O2. [5]
Enthalpy of formation of NaNO3 = -468 kJ/mol
Enthalpy of formation of NaNO2 = -369kJ/mol
Answer:
Explanation:
2NaNO₃ = 2NaNO₂ + O₂
NaNO₃ = NaNO₂ + 1/2 O₂
- 468 kJ -369 kJ 0 kJ
enthalpy of decomposition reaction
= - 369 - ( - 468 ) kJ
= 99 kJ / mol .
The periodic table is organized into groups and periods of elements. The characteristics of a certain group of elements are listed below. Which of these elements is in this group?
Characteristics of a group of elements
•is shiny
•is solid at room temperature
•has atoms with two valence electrons
A-silicone
B-lithium
C-strontium
D-aluminum
Answer:
C:Strontium
Explanation:
Please help
It’s super quick
Answer:
1. a
Explanation:
2. c
Answer:
1 is A number two is C
predict how many moles of nh3 would be made if 6.00 moles of h2 were used N2
Answer:
4 moles
Explanation:
The equation is 3H2 + N2 → 2NH3
so the ratio of moles would be
2:3 or 2/3
so 6*2/3 which is 4
hope this helped.
Answer:
4moles
Explanation:
Given parameters:
Number of moles of H₂ used = 6moles
Equation of the reaction:
N₂ + 3H₂ → 2NH₃
3 mole of H₂ was used to produce 2 mole of NH₃;
6 mole of H₂ will produce [tex]\frac{6x2}{3}[/tex] = 4 moles of NH₃
The number of moles of NH₃ produced is 4moles
PLEASE HELP!! (I will mark brainiest) (REAL ANSWERS ONLY PLEASE!)
In one paragraph, using your own words, describe the structure of DNA using the following terms: phosphate, sugar, pyrimidines, purines, and bonding.
The phosphate group of one nucleotide bonds covalently with the sugar molecule of the next nucleotide, and so on, forming a long polymer of nucleotide monomers. The sugar–phosphate groups line up in a “backbone” for each single strand of DNA, and the nucleotide bases stick out from this backbone. The carbon atoms of the five-carbon sugar are numbered clockwise from the oxygen as 1′, 2′, 3′, 4′, and 5′ (1′ is read as “one prime”). The phosphate group is attached to the 5′ carbon of one nucleotide and the 3′ carbon of the next nucleotide. In its natural state, each DNA molecule is actually composed of two single strands held together along their length with hydrogen bonds between the bases.
Answer:
Explanation:
The discovery that DNA is the prime genetic molecule, carrying all the hereditary information within chromosomes, immediately focused attention on its structure. It was hoped that knowledge
of the structure would reveal how DNA carries the genetic messages that are replicated when chromosomes divide to produce two identical copies of themselves. During the late 1940s and early 1950s, several research groups in the United States and in Europe engaged in serious efforts—both cooperative and rival—to understand how the atoms of DNA are linked together by covalent bonds and how the resulting molecules are arranged in three-dimensional space. Not surprisingly, there initially were fears that DNA might have very complicated and perhaps bizarre structures that differed radically from one gene to another. Great relief, if not general elation, was thus expressed when the fundamental DNA structure was found to be the double helix. It told us that all genes have roughly the same three-dimensional form and that the differences between two genes reside in the order and number of their four nucleotide building blocks along the complementary strands.
Now, some 50 years after the discovery of the double helix, this simple description of the genetic material remains true and has not had to be ap- preciably altered to accommodate new findings. Nevertheless, we have come to realize that the structure of DNA is not quite as uniform as was first thought. For example, the chromosome of some small viruses have single-stranded, not double-stranded, molecules. Moreover, the precise orientation of the base pairs varies slightly from base pair to base pair in a manner that is influenced by the local DNA sequence. Some DNA se- quences even permit the double helix to twist in the left-handed sense, as opposed to the right-handed sense originally formulated for DNA’s general structure. And while some DNA molecules are linear, others are circular. Still additional complexity comes from the supercoiling (further twisting) of the double helix, often around cores of DNA-binding proteins.
Likewise, we now realize that RNA, which at first glance appears to be very similar to DNA, has its own distinctive structural features. It is principally found as a single-stranded molecule. Yet by means of intra-strand base pairing, RNA exhibits extensive double-helical character and is capable of folding into a wealth of diverse tertiary structures. These structures are full of surprises, such as non-classical base pairs, base-backbone interactions, and knot-like configurations. Most remarkable of all, and of profound evolutionary significance, some RNA molecules are enzymes that carry out reactions that are at the core of information transfer from nucleic acid to protein.
Clearly, the structures of DNA and RNA are richer and more intricate than was at first appreciated. Indeed, there is no one generic structure for DNA and RNA. As we shall see in this chapter, there are in fact vari- ations on common themes of structure that arise from the unique physi- cal, chemical, and topological properties of the polynucleotide chain
What is represented in each block of the periodic tables?
the answer is c
it wants me to write a 20 letter explanation but ion got time for that
One ion is represented in each block of the periodic tables. Hence option C is correct.
What is periodic table?Periodic table is defined as a table with the chemical elements ordered by increasing atomic number, displaying the elements to show trends in their characteristics. The elements are arranged in the Periodic Table in accordance with their related chemical and physical characteristics. There are rows and columns in the table. The periodic table's vertical columns stand in for Groups. Periods are shown in the table as horizontal rows.
Ions are defined as any atom or collection of atoms that carries one or more electrical charges, either positive or negative. The positive ions are known as cation while the negative ions are known as anion. When an atom's number of protons and electrons is out of balance, ions are created.
Thus, one ion is represented in each block of the periodic tables. Hence option C is correct.
To learn more about periodic table, refer to the link below:
https://brainly.com/question/11155928
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