Which of these accurately describes a chemical reaction?
A. Products and reactants combine to form new reactants
B. Products and reactants combine to form new substances
C. Products combine to make reactants
D. Recatants combine to form products

Answer:

(NH4)2Se

Explanation:

The  chemical formula for  compound ammonium selenide is (NH₄)₂Se.

Here's a step-by-step explanation of how we arrive at this formula:

1. Ammonium ion: The ammonium ion is represented by the formula NH₄⁺. It consists of one nitrogen atom (N) bonded to four hydrogen atoms (H).

2. Selenide ion: The selenide ion is represented by the formula Se₂⁻. It consists of one selenium atom (Se) with a charge of -2.

3. Combining the ions: To form a neutral compound, we need to balance the charges of the ions. Since the ammonium ion has a charge of +1 and the selenide ion has a charge of -2, we need two ammonium ions to balance the charge of one selenide ion.

4. Formula: Therefore, the formula for ammonium selenide is (NH₄)₂Se, indicating that two ammonium ions are required for each selenide ion.

Thus, ammonium selenide has chemical formula of (NH₄)₂Se.

Learn more about chemical formula,here:

https://brainly.com/question/32018188

#SPJ6

Answer:

If Carbon Dioxide levels go up then so does air temperature

First we need to find the wavelength from the frequency using [tex]C = \lambda V[/tex]

so [tex]3.0e8 = \lambda * 2.2e16 Hz[/tex] which equals 1.36e-8 m then we use the formula [tex]E =h \frac{C}{\lambda}[/tex] we plug in [tex]E = 6.63e-34 * (3.0e8/1.36e-8)[/tex] and we get [tex]E = 1.46e-17[/tex]

so the energy is 1.46 x 10^-17 J.

Answer:

A, 1.5 × 10 ^–17 J

Explanation:

edge

Answer:

The larger the atom, the lesser the tendency for the atom to withhold its valence electrons.

Explanation:

The size of an atom is usually estimated in terms of its atomic radius. Across the period in the periodic table, the atomic radius decreases progressively from left to right. This is due to the progressive increase in the nuclear charge (i.e., the number of protons in the nucleus) without an attendant increase in the number of electronic shells.

Similarly, down the group, the atomic radius increases progressively from top to bottom due to the successive number of electrons' shells.

Thus, the larger the atom's radius, the smaller the Ionization energy because of the increasing shielding effect of inner shell electrons on the electron to be removed from the nuclear attraction.

Finally, we can conclude that as the atom becomes larger, the tendency to withhold the electrons on the outer shell decreases due to distance and the shielding/ screening effect.

Answer:

Explanation:

In order to be able to solve this question/problem efficiently one has to understand the the concept of acidity. Using the Bronsted- Lowry definition, Acids can be defined as any substance that has the ability of donating proton/ Hydrogen ions,H^+.

REASON BEHIND THE POSITIVELY CHARGED SURFACE:

The protons that acids produces will react with the shell of the eggs which contains a calcium compound. When these protons from acid react with the shell of the egg there is productions of Calcium ion, Ca^2+ and other materials such as water.

WHY MIGHT THIS RESULT IN A CHEMICAL REACTION WITH THE FOOD COLORING WHILE NOTHING SEEMED TO HAPPEN TO THE EGG I

THE WATER SOLUTION?

Nothing happens to the water solution because water is not acidic. The positive ions (produced by the reaction of protons with the egg shell) are able to reach with negative ions.

WHAY DOES THIS TELL YOU ABOUT THE CHARGE OF THE FOOD COLORING MOLECULES?

They are negatively charged.

Answer:

A) Potassium B) Boron C) Barium C) Neon

Explanation:

Answer: Plants have the ability to make the right amount of glucose to be used on nights or when there is a cloudy day. It can be kept in the plants leaves and other areas.

Explanation: pls mark brainiest thankss!!

Answer:

The nucleus (center).

Explanation:

The atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged). Atoms have different properties based on the arrangement and number of their basic particles.

Hope this helped. :D

Answer:

If the average kinetic energy of the particles (temperature) remains the same, the average force per particle will be the same. With more particles there will be more collisions and so a greater pressure.

Answer:

2. Oxidation number

Explanation:

In an atom, M, nuclide notation is expressed as:

ₓᵃMⁿ

Where a is mass number (Protons + neutrons)

x is atomic number (Protons)

And n is the charge of the atom (Protons - Electrons ; Oxidation number)

The atom Cu²⁺ has lost 2 electrons, changing, thus, its oxidation number.

Right answer is:

Answer:

Oxidation number

Answer:

its A and D

Explanation:

Answer:

The motorcycle's speed after three seconds of acceleration is 18 [tex]\frac{m}{s}[/tex]

Explanation:

Acceleration is a vector quantity that relates changes in speed to the time it takes to occur. Its unit of measurement, in the International System is meters per second squared [tex]\frac{m}{s^{2} }[/tex].  This is expresed as:

[tex]acceleration= \frac{change in speed}{time}[/tex]

Acceleration relates changes in speed with the time in which they occur, that is, it measures how fast changes in speed are:

In this case you know:

Replacing:

[tex]6 \frac{m}{s^{2} } = \frac{speed}{3 seconds}[/tex]

Solving:

speed= [tex]6\frac{m}{s^{2} }[/tex] * 3 seconds

speed= 18 [tex]\frac{m}{s}[/tex]

The motorcycle's speed after three seconds of acceleration is 18 [tex]\frac{m}{s}[/tex]

Answer:

1) Metalloids Metalloids, also called semiconductors, are the elements that border the zigzag line on the periodic table. Chemical Symbol Each square on the periodic table includes an element's name, chemical symbol, atomic number, and atomic mass.

2) Atom – the smallest particle into which an element can be divided and still be the same substance. 2. Electrons – the negatively charged particles found in all atoms.

3) Electrons are the negatively charged particles of atom. Together, all of the electrons of an atom create a negative charge that balances the positive charge of the protons in the atomic nucleus. ... The mass of an electron is almost 1,000 times smaller than the mass of a proton.

4) Carbon-13 (13C): The carbon isotope whose nucleus contains six protons and seven neutrons. This gives an atomic mass of 13 amu. six neutrons, resulting in an atomic mass of 12 amu.

5) Atoms are constructed of two types of elementary particles: electrons and quarks. Electrons occupy a space that surrounds an atom's nucleus. Each electron has an electrical charge of -1. Quarks make up protons and neutrons, which, in turn, make up an atom's nucleus.

6) Neutrons are the particles in an atom that have a neutral charge. They aren't positive like protons. They aren't negative like electrons.

7) The current model of the atom shows an atom that is mostly empty space. In the center is a small nucleus made of protons and neutrons.

8) The mass number of an atom is equal to the number of protons plus the number of neutrons that it contains. In other words, the number of neutrons in any atom is its mass number minus its atomic number. Although all atoms of a given element must have the same atomic number, they need not all have the same mass number.

9) Mendeleev arranged the elements in order of increasing relative atomic mass . When he did this he noted that the chemical properties of the elements and their compounds showed a periodic trend .

10) Letter: C

Answer:

Short answer 18x3=54 gram

Explanation:

When you express molecular mass (in case of molecule)/atomic mass(in case of atom) in gram it will be equivalent to one mole. For example:

12 gram Carbon atom = 1 mole of Carbon atom = N number of Carbon atom

16 gram Oxygen atom= 1 mole of Oxygen atom = N number of Oxygen atom

32 gram Oxygen molecule (O2) = 1 mole of Oxygen molecule (O2) = N number of Oxygen molecule (O2)

similarly 1 mole of water is equivalent to molecular mass of water x 3 that is 18x3=54 gram. It would constitute 3N molecules of water.

N: Avogadro's number : 6.022140857 × 10^23

Explanation:

According to the mole concept ,the mass of 3 moles of H₂O or water is 54 g.

Mole is defined as the unit of amount of substance . It is the quantity measure of amount of substance of how many elementary particles are present in a given substance.

It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on the type of substance. Amount of elementary entities in a mole is called as Avogadro's number.

It is widely used in chemistry as a suitable way for expressing amounts of reactants and products.For the practical purposes, mass of one mole of compound in grams is approximately equal to mass of one molecule of compound measured in Daltons .Molar mass has units of gram per mole . In case of molecules, where molar mass  in grams present in one mole  of atoms is its atomic mass.

Number of moles is obtained as, mass/molar mass.Substituting number of moles as 3 and molar mass as 18 g mass=18×3=54 g.

Thus, the mass of 3 moles of H₂O is 54 g.

Learn more about moles,here:

https://brainly.com/question/26416088

#SPJ2

Answer:

the answer is b, which is one

Answer:

There is 13 atoms in total.

Explanation:

There is 2 potassiums, 4 borons and 7 oxygens.

So 2 + 4 + 7 = 13 atoms

Hope this helps!

Answer:

wassup bro

Explanation:

It’s mid ocean ridges

Answer:

So, to determine the number of neutrons in atom, we only have to subtract the number of protons from the mass number. # of neutrons = Mass Number - Number of Protons To be able to apply this formula, refer to the atomic number and atomic weight of the elements. These two are listed in the Periodic Table of Elements.

Explanation:

I'm new to brainly so I hope this helped

Answer:

Compound.

Explanation:

Salt is an ionic compound. How do I know?

When dissolved in water (water is a covalent compound), then salt will allow electricity to move through it because it is a conductor.

Other reasons:

High melting point.

High boiling point.

Strong bond.

Transfers electrons.

Made of a metal or nonmetal.

Etc.

Answer:

d is physical

f is chemical

Explanation: In an isotonic environment, the relative concentrations of salute and water are equal on both sides of the membrane period there is no water movement, so there is no change in the size of the cell period when a cell is placed in a hypnotic environment, water will never enter the cell and the cell will swell

In order to determine an objects location, you need to know the speed of the object by which it is moving.

Speed (commonly referred to as v) of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval;the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Speed is not the same as velocity.

Speed has the dimensions of distance divided by time. The SI unit of speed is the metre per second (m/s), but the most common unit of speed in everyday usage is the kilometre per hour (km/h) or, in the US and the UK, miles per hour (mph). For air and marine travel, the knot is commonly used.

Learn more about speed,here:

https://brainly.com/question/30462853

#SPJ3

Answer:

They are called energy levels.

Explanation:

Explanation:

The atomic number of an atom is also the number of proton in an atom.

Answer:

2,1,1,1

Explanation:

4,2,2,2 (simplify)

Answer:

B. BF3

Explanation:

I did summoning jutsu on it and got it correct

Answer:

NiSO4

Explanation:

Sulphur has got 2 valence electrons that it gains and on the exchange of the valence electrons with Nickel, which provides a number of valence electrons that cancels easily with those of sulphur, the we shall have the remainder of four electrons at the the bass of the formula

Answer:

Fossil B was found at a depth of 185 meters below the Earth's surface, while fossil A was found at a depth of 50 meters below the Earth's surface.

Explanation:

Because if fossil B was found at a lower depth then it would be older than fossil A

Hope this helps, have a good day :)

Answer:

Fossil B was found at a depth of 185 meters below Earth's surface, while fossil A was found at a depth of 50 meters below Earth's surface.

Explanation:

I hope this is an answer choice but this would support fossil B being older than fossil A bc the deeper the fossils are in the earth’s surface means that its older.

One way to rephrase it is to say: "All life depends on photosynthesis because plants use the sun's energy to make oxygen for animals to breathe. Also, animals rely on plants for energy when they eat the plants"