what is the lewis structure for RnF2

1. Isotopes: the same element, the same atomic number, but different mass numbers

Atomic mass: the average atomic mass of all its isotopes

The mass of an atom of carbon-12= 12 amu ( atomic mass unit) because it has a stable nucleus

[tex]\tt RAM~X=\dfrac{the~average~mass~of~1~atom~X}{\dfrac{1}{12}\times mass~of~atom~C-12 }[/tex]

So RAM relative to isotopes Carbon-12 (C)

2. Ionic Formula is formed from cation(positive charge) and anion(negative charge)

Cation : Na⁺ ( positively charged 1)

Anion : SO₄²⁻ (negatively charged 2)

The anion cation's charge is crossed , then the compound :

[tex]\tt \boxed{\bold{Na_2SO_4}}[/tex]

3. pH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.  

pH = - log [H⁺]  

[H⁺]   = 0.00001 M = 10⁻⁵ M

[tex]\tt pH= -log 10^{-5}\\\\pH=5~log~10\\\\pH=\boxed{\bold{5}}[/tex]

Answer:

Explanation:Table salt is sodium chloride and has the chemical formula of NaCl. What is the ratio of sodium atoms to chlorine atoms? (8.5D)

Answer

А 2:1

B

1:1

С

1:2

D

3:1

Answer:

god loves you i love u

everybody loves you

Answer:

A-cycles of the moon

Explanation:

The people of Ancient Greece, Rome and China counted their year based on a 12 moon cycle ( that is, about 354 days). A 13th cycle of the moon is included so that the lunar year remains in step with the seasons of the year.

Today, the Gregorian calendar is mostly used around the world. This calendar was

actually adapted from an earlier lunar version. Ancient civilizations used the phases of the moon to help identify the seasons.

The major difference between the lunar calendar and the solar calendar is the kind of celestial body that is used to determine time.

Answer:

See explanation

Explanation:

I believe that the aim of the scientist is to determine the effect of a cancer drug on mice with lymphoma. In this experiment, the mice with lymphoma are exposed to the drug. This is the treatment in the experiment. A control group of mice having lymphoma is not exposed to this treatment, this is the control group. This control group establishes a baseline for the study.

By comparing the outcome of the experimental and control groups, the effect of a cancer drug on mice with lymphoma can be determined.

Answer: D. Are the first to receive energy from a plant.

Explanation: Paying attention to the trophic level in which the food chain occurs is key. Producers are the ones that receive energy directly from the sun. They also make their own food using photosynthesis. A decomposer is the one who breaks down dead matter into chemical nutrients. Therefore, Primary consumers are the first to receive energy from a plant.

I hope this helped!

Good luck <3

Answer:

A) Paired

Explanation:

hdhwmenrnbdbd

Answer:

yes

Explanation:

A. The rate of reaction A is lower

The reaction rate (v) shows the change in the concentration (reduction of reactants and product additions ) per unit time

Can be formulated:

Reaction: aA ⇒ bB

[tex]\large{\boxed{\boxed{\bold{v~=~-\frac{\Delta A}{\Delta t}}}}[/tex]

or

[tex]\large{\boxed{\boxed{\bold{v~=~+\frac{\Delta B}{\Delta t}}}}[/tex]

A = reactants

B = product

v = reaction rate

t = reaction time

Time of reaction A : 12 s

Time of reaction B : 2 s

Because reaction speed/the rate of reaction is inversely proportional to the time, then A. The rate of reaction A is lower

Answer:

No, it is not.

Explanation:

Answer:

8

Explanation:

Answer: The sun is closer to the Earth is the summer and farther in the winter causing it to be hotter than it is colder in the summer and vise versa for the other question.

Explanation: I learned it ;)

Explanation:

The earth is tipped on its axis, 23.5 degrees in respect to the sun. In the summer time, the northern hemisphere has slightly more hours of daylight because of this, becoming more extreme as one goes north. If you go far enough north, there is 24 hours of sunlight in high summer.

So the average temperature is higher, because there is sunlight is present for more hours and the earth is warmed on balance.

At the same time, the south pole is in shadow, so the southern hemisphere has winter in June.

Six months later, the 23.5 degree tilt has the north pole facing away from the sun, and with fewer daylight hours, the temperature cools progressively. Meanwhile, the southern hemisphere is having it’s summer in December.

Answer:

Below.

Explanation:

This is the combustion of the hydrocarbon propane.

C3H8 + 5O2 --> 3CO2 + 4H2O

Answer:

C₃H₈ + 5O₂ = 3CO₂ + 4H₂O

Explanation:

This is called a complete combustion reaction because CO₂ and H₂O are produced. To balance any equation, you have to make sure there is the same number of each element on both sides.

Answer:

I think it's D

Explanation:

I'm so sorry if that's wrong, hope it helps!

The temperature at which the vapor pressure of a substance equals the air temperature at sea level. Therefore, the correct option is option D.

The temperature at which a liquid's vapor pressure equals the pressure around it and the liquid transforms into a vapor is known as the boiling point of a material.

A liquid's boiling point changes based on the atmospheric pressure in the area. Lower pressure, or partial vacuum, results in a liquid's boiling point being lower than it would be under atmospheric pressure. The temperature at which the vapor pressure of a substance equals the air temperature at sea level.

Therefore, the correct option is option D.

To know more about boiling point, here:

https://brainly.com/question/28986258

#SPJ5

Answer: you need to know the Mass (grams) of the object, and its Volume (measured in mL or cm³). Divide the mass by the volume in order to get an object's Density. How can you tell if something will float in water?

Explanation:

Answer:

To find the density of an object you need to know the Mass (grams) of the object and its Volume. Divide the Mass by the Volume in order to get the object's density.

Good luck! Hope this helped :)

Answer:

No it is not, most bacteria is very helpful, it helps the body function and fight off diseases when the body is sick. Sometimes the good bacteria can't fight off the bad bacteria and will cause you to have to buy antibiotics. The antibiotics give the body a huge advantage at fighting off the disease and the body goes back to normal.

Answer:

I’d say Table 4, because it stays as the same.

Explanation:

Answer : b. mixture

Element and compound are included in pure substance where the composition is the same in each part

Elements are made up of 1 type of atom, while the compounds of 2 or more types of atoms , both can be represented in the form of chemical symbols

A mixture is a combination of substances. The properties of a substance in the mixture component are unchanged

The mixture can be a homogeneous mixture or a heterogeneous mixture

Solution including into Homogeneous mixture, while suspension into a heterogeneous mixture

So a term that could refer to heterogeneous matter : b. mixture

Answer:

Explanation:

To maintain homeostasis, unicellular organisms grow, respond to the environment, transform energy, and reproduce. The cells of multicellular organisms become specialized for particular tasks and communicate with one another to maintain homeostasis. All body systems work together to maintain homeostasis.

Being made up of many cells helps large organisms maintain homeostasis as follows:

Cells act in a coordinated way in the organisms and they prevent changes in the environment from interfering with their functioning.

The existence of large complex organisms was only possible thanks to the evolution of an internal environment, whose physical and chemical conditions must be maintained at relatively constant levels, favorable for cells.

The cells were able to specialize in tasks that would help maintain specific aspects of the internal environment.

For example, some cells organized into tissues specialized in maintaining the balance of salt and water; others, in providing nutrients; while others, in maintaining appropriate levels of oxygen and carbon dioxide.

In addition, specialized tissues and organs form systems within the internal environment of the organisms.

For example, the digestive system that provides nutrients; while the cells related to the circulation, among other things, distribute oxygen and nutrients.

In this way, specialized cells and tissues must continuously correct the physical and chemical composition of the internal environment, so that it remains conducive to life.

The maintenance of relatively constant conditions in the internal environment is what is called homeostasis.

Therefore, we can conclude that being composed of many cells helps large organisms to conserve specific aspects of the internal environment to maintain its homeostasis.

Learn more here: https://brainly.com/question/3888340

Answer:

1:C

2:D

3:E

4:A

5:B

Explanation:

Answer: it’s A

Explanation:

Answer:

flammable

that's the first thing that popped in my head

Another term for the ability to burn is combustibility. Combustibility refers to the ability of a substance to ignite and burn in the presence of oxygen.

Combustibility is a property that varies among different materials.When a substance is combustible, it means that it can undergo a chemical reaction called combustion, which involves the combination of the substance with oxygen to produce heat, light, and often smoke or flame. Combustion is a rapid oxidation process that releases energy in the form of heat and light.

Examples of combustible materials include wood, paper, gasoline, and natural gas. These substances have the ability to burn when exposed to a spark, flame, or heat source.

It is important to note that not all materials are combustible. Some materials, such as metals, may be non-combustible and do not easily catch fire.

It also allows us to take appropriate precautions when handling and storing combustible substances to prevent accidents and fires.

Learn more about combustibility,here:

https://brainly.com/question/15117038

#SPJ6

Answer:

b or d

Explanation:

Answer:

I not understand your questions

Answer:

i think is A.

Explanation:

Answer:

the answer is

Explanation:

A change in state involves a change in volume.

2. Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons.

3. Electrons

4. Titanium- Ti

5. a. e and p = 35, n = 45

b. e and p = 46, n = 60

c. e and p = 55, n = 78

6. Barium - atomic number = 56 and mass = 138

Hope it helps :)

Mark it Brainliest pls :)

Answer:

i believe this is ur answer-138

Explanation:

hope this helps :)

Answer:

the number of neutrons for silicon is 14