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The options are:
A. Nitrogen.
B. Neon.
C. Hydrogen chloride.
D. Sulfur dioxide.

Answer:

Growth of weeds and grasses

Explanation:

The part of the garden, probably left to rest by the Gardner, would start experiencing a legion of invasive plants. Giant weeds and grasses could be seen, and brambles and tree seedlings could also sneak in.  

Some Gardeners would recommend the use of herbicides to restore order to an abandoned garden even though certain scientists are of the opinion that chemicals may not offer a sound solution to the problem.  

Answer:

Among the given reactions,

a. Ag+FeCl 3

b, Zn + CaO

C. Ba+Na 2 CO 3

d . Cr+KNO3

which reaction is likely to take place based on the reactivity series?

Explanation:

The metal reactivity series is:

Li > K> Ba >Ca>Na > Mn > Zn > Cr> Fe> Cd Ni > H > Sb > Cu > Ag > Pd > Hg > Pt

The highly reactive metal will displace the less reactive metal from its compound during a displacement reaction.

a. Ag+FeCl 3

Ag is less reactive than Fe, so Ag cannot displace Fe from its compound.

This reaction also does not occur.

b, Zn + CaO

Zn is less reactive than Ca, so it cannot displace Ca from its compound.

This reaction does not occur.

C. Ba+Na 2 CO 3

Ba is more reactive than Na, so Ba displaces Na from its compound.

This reaction is possible.

d . Cr+KNO3

Cr is less reactive than K, so it cannot displace K from its compound.

Hence, This reaction is not possible.

Answer:

option c) Ba+Na 2 CO 3 -> BaCO3 +2Na

Answer:

Answer:

its answer is nitric acid...

Answer:

"How to prevent the collapse of the dam that contains water from heavy rains?"

Explanation:

Scientists must work to create innovations capable of bringing benefits to human life and combating disadvantageous and harmful situations. The overflow of dams is something very harmful, as the resulting flooding can cause structural, economic and even public health problems. When this overflow is caused by natural elements, such as heavy rains, the work of scientists in solving these issues is even more important and necessary. In order to resolve the dam failure caused by excess rainwater, scientists must work to answer the following question:

"How to prevent the collapse of the dam that contains water from heavy rains?"

Answer: increasing the number of collisions between reactants

Explanation:

A reaction is possible due to collisions between the reactants to create products. If we increase the concentration of reactants then that means that we are increasing the molecules of the reactants which would give them more chances to collide and make products.

For instance, using a non-chemistry example, if there are few cars in a large city, the accidents there will be less because the cars will have such space that they wouldn't collide with each other. If the number of cars in the city is increased however, there is now less space and more chances for cars to collide.

Explanation:

ionisation energy decrease down the group as the atomic radius increases. Nuclear charge increases. Number of shell increases so the electron will experience more shielding so it would be easier for the atom to loss electron.

bez number of particles in reaction increases so randomness or entropy increase.

as entropy is the degree of randomness of particles in a system

Answer:

Bones aren't made of calcium metal. Bones are a collegun structure filled in with mostly calcium carbonate and some calcium phosphate

Answer:

Bones aren't made of calcium metal. Bones are a collegun structure filled in with mostly calcium carbonate and some calcium phosphate

Explanation:

I hope this helps

Answer:

yes

Explanation:

as it had got crushed down in the dinosaurs age

Answer:

Matter or energy can change from one form to the other

Explanation:

The law of conservation of energy states that energy can neither be created nor destroyed but can only be transformed i.e. changed from one form to another. For example, mechanical energy can be changed to electrical energy.

Likewise, the law of conservation of mass/matter states that matter can not be destroyed or created but can change via physical or chemical means to conserve it. For example, matter can change from liquid state to gaseous state.

From the above two laws, it can be said that "matter or energy can change from one form to the other".

Answer:

formula for calculating mass is

first U will HV to find number of moles

m=n×M

Answer:

sry I don't know much about chemistry

Answer:

0.3 sec : -0.4 m

0.5 sec: -1.2 m

0.7 sec: -2.3 m

Explanation:

0.3 sec: 1/2(-9.3 m/s^2)(0.3 s)^2 = -0.4 m

0.5 sec: 1/2(-9.3 m/s^2)(0.5 s)^2 = -1.2 m

0.7 sec: 1/2(-9.3 m/s^2)(0.7 s)^2 = -2.3 m

Answer:

ExplaAt high temperatures MgCO3 decomposes to magnesium oxide and carbon dioxide. This process is important in the production of magnesium oxide. This process is called calcining: MgCO3 → MgO + CO2 (ΔH = +118 kJ/mol)

nation:

Answer:

17. 3,101.922

18. 1.2447441822

19. 288,057.12

20. 0.74497354

Answer:

Because the scientific knowledge itself helps solve many basic human needs and it also improves how humans live and their standards. For example, without science medications wouldn´t exist and many technological devices we use now-a-days. We´re surrounded by science, we just don´t really notice it.

Answer:

Explanation:

By the kinetic molecular theory (particle model), all matter consists of particles, there are spaces between the particles, the particles are in constant random motion, and there are forces of attraction and repulsion between the particles.

Furthermore, temperature is defined to be a measure of the average kinetic energy of the particles.

Evaporation is a change of phase from liquid to gas explained as follows :

When particles in the liquid phase are heated, they gain kinetic energy and move faster and further apart. Eventually they have enough energy to escape the forces of attraction holding them together in the liquid phase and they move very fast and far from each other and exist in the gaseous phase.

Answer:

Choice D) 1 mL pipet

Explanation:

If you are trying to extract 0.02 mL of HCl, you are going to need a piece of equipment that can measure very small units. Thus, Choice D would be the correct answer.

Answer:

Rare earth elements are lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium - that appear in low concentrations in the ground.

Explanation:

The rare earth elements (REE) are a set of seventeen metallic elements. These include the fifteen lanthanides on the periodic table plus scandium and yttrium. Rare earth elements are an essential part of many high-tech devices.

Answer: The statement the  [tex]n^{th}[/tex] shell holds a minimum number of [tex]2n^{2}[/tex] electrons is true.

Explanation:

The alphabet 'n' denotes the principal quantum number whose value can be equal to 1, 2, 3, and so on but can never be zero.

Basically, 'n' is the number of shell of an atom and total number of orbitals present in a shell is [tex]n^{2}[/tex].

Each orbital can hold up to a maximum of wo electrons. Hence, the [tex]n^{th}[/tex] shell can hold a minimum number of [tex]2n^{2}[/tex] electrons.

Thus, we ca conclude that the statement the  [tex]n^{th}[/tex] shell holds a minimum number of [tex]2n^{2}[/tex] electrons is true.

Answer:

C. 3.37 x 10^-19 J

Explanation:

Answer:ehwusvudhwdvwxkwvbxbwxbxiwhxjvwxjvxwjxvjxvwxiwvxiwzgiwxvwjsbwis

HOPE IT HELPS IF YOU LIKE MY ANSWER THEN MARK ME AS BRAINLIEST ;-);-)

The first diagram shows the covalent bonds most likely form in a phosphorous trichloride molecule. Hence, option A is correct.

Covalent bonds can be polar or nonpolar depending on the electronegativity difference between the atoms involved. In a nonpolar covalent bond, the electrons are shared equally between the atoms. In a polar covalent bond, the electrons are shared unequally.

Phosphorus trichloride (PCl₃) is a covalent compound that consists of one phosphorus atom and three chlorine atoms. The three chlorine atoms are located in a plane that is perpendicular to the phosphorus atom, forming an equilateral triangle with bond angles of 120°.

The molecule has a trigonal pyramidal shape, with the phosphorus atom at the apex and the three chlorine atoms at the base of the pyramid. The fourth hybridized orbital of phosphorus contains a lone pair of electrons that is located above the trigonal plane, giving the molecule a distorted tetrahedral geometry.

Thus, option A is correct.

To learn more about the covalent bond, follow the link:

https://brainly.com/question/10777799

#SPJ2

Answer:

6.3moles

Explanation:

The balanced equation of the reaction described above between aqueous magnesium chloride and sodium metal is as follows:

MgCl2(aq) + 2Na(s) → 2NaCl(aq) + Mg(s)

From the above equation, 2 moles of sodium metal (Na) produces 1 mole of Magnesium metal (Mg)

Hence, 12.6 mol of Na will produce (12.6/2) mol of Mg.

12.6/2 = 6.3moles of Mg metal.

Respuesta:

199.5 g

Explicación:

Paso 1: Escribir la reacción balanceada

2 Al + 3 H₂SO₄ ⇒ Al₂(SO₄)₃ + 3 H₂

Paso 2: Calcular la masa pura de 50 g  de Al

Aluminio tiene 10% de impurezas, es decir, 10% de 50 g = 5 g. Luego, tiene 50 g - 5 g = 45 g de Al puro.

Paso 3: Calcular la masa teórica de Al₂(SO₄)₃ obtenida a partir de 45 g de Al

La relación de masas de Al₂(SO₄)₃ a Al es 342:54.

45 g Al × 342 g Al₂(SO₄)₃/54 g Al = 285 g Al₂(SO₄)₃

Paso 4: Calcular la masa real de Al₂(SO₄)₃ obtenida

El rendimiento de la reacción es de 70%.

285 g × 70% = 199.5 g

Answer:

Sodium is very reactive in nature. When exposed in air, it automatically forms Na2O. When it is put in water it reacts vigorously and starts burning on water. Due to the above reasons Sodium is called an active metal

Explanation: hope this helps pls mark as brainliest ty

Answer:

Grand Tourer  Injection

Answer:

Awnser is A

Explanation:

Answer:

Hello There!!

Explanation:

The answer is↬O A. A measurement indicating how acidic a solution is.

hope this helps,have a great day!!

~Pinky~