7th grade help me plzzzzz

Answer:

atomic number of 12 is MG

Explanation:

Magnesium

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.

Answer:

forensic scientist

Explanation:

forensic science is the discipline in which professionals use scientific means to analyze physical crime evidence. this evidence is then presented in court in order to help determine the innocence or guilt of a specific suspect.

Answer:

Its a forensic scientist :D

Explanation:

I took a test and got it wrong but it showed the right answer and its a forensic scientist

(don't ask how i got it wrong i was rushing!!)

Answer:

light bulb B

Explanation:

more resistance

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.

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)

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 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.

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

#SPJ6

Answer:

[N₂O₄] = 0.00411 M

[NO₂] = 0.0918 M

Explanation:

In the reaction of: N₂O₄(g) ⇌ 2 NO₂(g) If the equilibrium constant is Kc = 0.513 and the initial concentration of N₂O₄ = 0.0500 M. What are the equilibrium concentrations of N₂O₄ and NO₂ under these conditions?

Step 1: Given data

Initial concentration of N₂O₄: 0.0500 M

Equilibrium constant (Kc): 0.513

Step 2: Make an ICE chart

        N₂O₄(g) ⇌ 2 NO₂(g)

I        0.0500           0

C           -x              +2x

E      0.0500-x        2x

Step 3: Find the value of "x"

The equilibrium constant is:

Kc = [NO₂]² / [N₂O₄]

0.513 = (2x)² / (0.0500-x)

4x² + 0.513 x -0.02565

We solve for x and we get x₁ = 0.0458942 and x₂ = −0.558894 (neglected).

Step 4: Calculate the concentrations at equilibrium

[N₂O₄] = 0.0500-x = 0.00411 M

[NO₂] = 2x = 0.0918 M

Answer:

Conduction

Explanation:

Answer:

Conduction is correct

Explanation:

Answer:

Explanation:

The volume of a substance when given the density and mass can be found by using the formula

[tex]volume = \frac{mass}{density} \\ [/tex]

From the question we have

[tex]volume = \frac{65}{5.45} \\ = 11.926605...[/tex]

We have the final answer as

Hope this helps you

Answer:

2

Explanation:

BIonary bi means 2

i hope this helps :)

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.

okay so the  Answer is c

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

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

Answer:

X represents London dispersion forces, and Y represents dipole-dipole forces.

Explanation:

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.

Answer:

Covalent compound

Explanation:

It is formed by covalent bonds, in which the atoms share a pair of valence electrons

Answer:

C:Strontium

Explanation:

Answer:

C

Explanation: I think

Answer:

salt is a very well known seasoning

Explanation:

hope this helped :)

Answer:

1. a

Explanation:

2. c

Answer:

1 is A number two is C

Answer:

Pb²⁺(aq) --> Ni²⁺(aq)

Explanation:

The equation of the reaction is given as;

Ni(s) + Pb(NO₃)₂(aq) --> Pb(s) + Ni(NO₃)₂(aq)

In writing the ionic equation, we break the aqueous compound into ions. The solid and liquid compounds are ignored.

We have;

Pb²⁺(aq)  + NO₃²⁻(aq) -->  Ni²⁺(aq)  + NO₃²⁻(aq)

Canceling the spectator ions;

Pb²⁺(aq) --> Ni²⁺(aq)

Answer:

Ni(s)+Pb2+(aq)→Ni2+(aq)+Pb(s)

Explanation:

The complete ionic equation of this reaction is

Ni(s)+Pb2+(aq)+2 NO−3(aq)→Ni2+(aq)+2 NO−3(aq)+Pb(s)

The nitrate ions are spectator ions and can be removed from the equation, giving us

Ni(s)+Pb2+(aq)→Ni2+(aq)+Pb(s)

Answer:

6 atoms

Explanation: