Which element is this.Its shiny,Is solid at room temperature, has atoms with two valence electrons?A:Lithium B:Strontium C:Aluminium D:Silicon

Answers

Answer 1

Answer:

Strontium

Explanation:

STRONTIUM

Strontium is a chemical element that is non radioactive and its occur naturally. It is a shiny and silvery white metal that have atomic number of 38 and it belong to group 2 member of the periodic table which is why it have two valence electrons. It is a solid metal at room temperature.

About 99% of Strontium is found in bones. It help to make new bones in humans by replacing the old bones.

Therefore, it is strontium.

Answer 2

Strontium is the element which is shiny, solid at room temperature and has two electrons in its outermost shell.

The atomic number of Strontium is 38. In the first shell, there are two electrons, in the second and fourth shell has space for 8 electrons so these shells are filled with electron whereas third shell has 18 electrons and the fifth shell has 2 electrons. Strontium belongs to second group i.e. alkaline earth metals due to which it has two valance electrons in its outermost shell.

https://brainly.com/question/18374119


Related Questions

how does litmus indicator work​

Answers

Answer:

The substance which responds to the change in the concentration of the hydronium ions in solution by changing its color is known as an indicator.

A substance can change into a new kind of molecule when:

Answers

Answer:

Chemical changes cause a substance to change into an entire substance with a new chemical formula. Chemical changes are also known as chemical reactions. The “ingredients” of a reaction are called reactants, and the results are called products.

Hope it helps

what is atomic radius​

Answers

Explanation:

The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Three widely used definitions of atomic radius are: Van der Waals radius, ionic radius, and covalent radius

HELP!! URGENT ASAP!! WILL GIVE BRAINLIEST TO FASTEST ANSWER!!

Answers

Answer:

This shoes the soda lime defusing to limewater turning into germinating seeding which defuses back to limewater

Explanation:

A cube of metal has a mass of 5.05 x 10°g and its density is known to be 12.77 g/mL, what is the volume of this metal?
A 395.5 mL
B. 2.529 mL
C. 63,910 mL
D. 64.48 ml

Answers

Answer:

Explanation:

option A is correct

Identify the choice that best completes the statement or answers the question.
Banana slugs live on the ground in moist forests of the Pacific Northwest. They consume and
break down a variety of materials, including small dead animals and rotting leaves. Which
term describes banana slugs?
O carnivores
O consumers
O decomposers
O producers
PLEASE HELP!!!

Answers

The answer would be decomposers

Which pair of symbols represents nuclei with the same number of neutrons?
A. 56 Co and 580
B. 57Co and 58Ni
c. 57Fe and 58 Ni
D. 57Mn and 57Fe

Answers

Answer:

B

Explanation:

Mass number  = number of neutrons + number of protons

Atomic number is the number of protons in the nucleus.  

58Ni   : 58 is the number of neutrons + number of protons

atomic number of Ni is 28.  Thus,  58 -28 = 30 neutrons

57Co ;  57 is the number of neutrons + number of protons

number of Co is 27. Thus, 57 – 27  = 30 neutrons

Deciding that she was thirsty, Ms. Smith decided to mix up some lemonade using 2 tablespoons of lemonade, and 2 cups of water. What is the solute and solvent?

Answers

Explanation:

solute is the substance being dissolved so that is the 2 tablespoons of lemonade and the 2 cups of water is the solvent.

After lab, all of Darrel's friends looked at his data and laughed and laughed. They told him that he was 30.8% too low in the boiling point he had just recorded. He had recorded a boiling point of 50o C on his data sheet. What is the correct boiling point of the liquid he was working with in lab?

Answers

Answer:

100°

Explanation:

For a boiling point is it always 100°

Radon-222 is an alpha emitter with a half life of 3.82 days.

1. What is the mass number of the daughter isotope?
2. What is the element symbol of the daughter isotope?
3. What is the atomic number of the daughter isotope?​

Answers

The daughter isotope (a decay product): Polonium (Po)

Further explanation

Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,  

alpha α particles ₂He⁴ beta β ₋₁e⁰ particles gamma particles γ positron particles ₁e⁰

Radon-222 emits alpha α particles ₂He⁴  , so the atomic number decreases by 2, mass number decreases by 4

Reaction

[tex]\tt _{86}^{222}Rn\Rightarrow _{84}^{218}+_2^4He[/tex]

1. The mass number of the daughter isotope = 218

2 and 3. If we look at the periodic system, the element with atomic number 84 is Polonium (Po)

lonic bonding
10. If two atoms that differ in electronegativity combine by chemical reaction and
share electrons, the bond that joins them will be
(1 Point)
ionic bond
polar covalent
nonpolar covalent
a hydrogen bond

Answers

Answer:

polar covalent

Explanation:

If they do not equally share the electron then it is polar and covalent bonds share electrons

The diagram shows a model of an animal cell. Explain how you'd modify the model to show the structures in a plant cell.

Answers

Answer:to show the structures of a plant cell,add a cell wall around the membrane and increase the size of the vaculoe insidethe cell, draw green ovals to represent chloroplasts.

Explanation:

Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below. A purple center outlined in black with two concentric black circles around the center, the inner circle having 2 small green balls on it and the outer circle having 8 small green balls on it. What experimental evidence led scientists to change from the previous model to this one? A few of the positive particles aimed at a gold foil seemed to bounce back. The colors of light emitted from heated atoms had very specific energies. Experiments with water vapor showed that elements combine in specific proportions. Cathode rays were bent in the same way whenever a magnet was brought near them.

Answers

Answer:

B: The colors of light emitted from heated atoms had very specific energies.

Explanation:

dont know if its the same question i had on edg but i think its B. Sorry if i didnt understand the question :)

Answer:

b

Explanation:

Name for each compoud
1.CO
2.H2SO4
3CaCO3
4 H202
5NaF

Answers

1. Carbon monoxide
2. Sulfuric acid
3. Calcium carbonate
4. Hydrogen peroxide
5. Sodium fluoride
hope this helps (:

Write the correct electron configurations for the following:
ments
ions
• Na (atomic # 11)
• Fe (atomic # 26)
• As (atomic # 33)
• F (atomic #9)
• Co (atomic #27)
• Ag (atomic # 47)
• K (atomic # 19)
• Cu (atomic # 29)
• Si (atomic # 14)

Answers

Answer:

Ag

Explanation:

atomic 33 because it what what sence

Na- 1s^2 2s^2 2p^6 3s^1

Fe- 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^6

As- 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^3

F- 1s^2 2s^2 2p^5

Do 2. A student determines that there are 1.3 x 1025 molecules of an unknown
substance in a 968 g sample. Which compound most likely represents this
unknown substance?
CO
CIO
2)
CO2
N203
CLEAR ALL

Answers

Answer:

The correct option is;

CO₂

Explanation:

The given information are;

The number of molecules in the substance = 1.3 × 10²⁵

The mass of the substance = 968 g

Therefore, we have;

The number of molecules in one mole of a substance = 6.02 × 10²³

The number of moles present = (1.3 × 10²⁵)/(6.02 × 10²³) ≈ 21.595 moles

Therefore, 968 g = 21.595 moles

1 mole = 968/21.595 = 44.826 g

The mass of one mole of the substance = 44.826 g

Therefore the mass of one mole of the substance is closely related to the mass of one mole of CO₂ which is 44.01 g/mol.  

The correct option is CO₂

The calculation is as follows:

The number of molecules in one mole of a substance should be = 6.02 × 10²³

And,

The number of moles present is

= (1.3 × 10²⁵)/(6.02 × 10²³)

≈ 21.595 moles

Now

1 mole = 968/21.595 = 44.826 g

The mass of one mole of the substance = 44.826 g

So,  the mass of one mole of the substance is closely related to the mass of one mole of CO₂ i.e.  44.01 g/mol.  

Learn more: https://brainly.com/question/1504221?referrer=searchResults

The first chemists, philosophers like, Aristotle were from which country?

Answers

Answer:

greece

Explanation:

aristole was particularly from stagria, greece. but most early philosophers are from greece

348 g of water starting at 4.0°Celsius is heated until his temperature is 37°Celsius. Calculate the amount of heat energy needed to cause this rise in temperature

STEP BY STEP EXPLANATION!!

Answers

Answer:

48.049 kJ or 48049 J

Explanation:

Hello again.

So we know the formula [tex]q = mc\Delta t[/tex]. c is the heat capacity but this time, it is not given. However, water has a very well known heat capacity which is 4.184 J/(g°C). This is in fact the number we refer to a calorie which is the amount of energy you burn that can raise the temperature of 1g of water by 1°C. So, plugging in values, you get the above. But double check if I am wrong.

The amount of heat energy needed to cause this rise in temperature is 48.049 kJ or 48049 J.

What is heat energy?

Heat is the energy that moves from one body to another when temperatures are different. Heat passes from the hotter to the colder body when two bodies with different temperatures are brought together.

A given amount of matter's heat capacity is the amount of energy needed to raise its temperature by one degree Celsius.

The heat energy will be calculated by the formula

Q = m•C•ΔT

Where c is the heat capacity.

The m is the mass

T is the time

Mass is 348 grams

Temperature is 37°C

The change in temperature is 4.0°C to 37°C

The heat capacity of water is 4.184

Q = 348 x 4.184 x -33 = 48049.056.

Therefore, the amount of heat energy needed is 48.049 kJ or 48049 J.

Learn more about heat energy, here:

https://brainly.com/question/10162784

#SPJ2

How to separate these pure substance?if it is not possible, please write cannot be separate

Oxgen
Water
Gold
Carbon Dioxide
Carbon​

Answers

Answer:

Oxgen- cannot be separated

Water - chemical change

Gold - cannot be separated

Carbon Dioxide - chemical change

Carbon​ - cannot be separated

Explanation:

A pure substance, which can either be an element or a compound, contains only one type of such element or compound. In opposition to a mixture, pure substances cannot be separated by physical means.

- Elements as a pure substance cannot be separated because it contains only one type of atom. However, compounds contain two or more types of atoms, and hence, can only be separated into its individual atoms via chemical means.

In this question, oxygen (O2), Gold (Au) and carbon (C) are all elements and hence cannot be separated. Carbon dioxide (CO2) and water (H2O) are compounds because they contain two different atoms respectively, hence, can be separated into individual atoms.

Fill in the blanks: a substance that undergoes a ______ change will always result in something new that has ________ properties than what it started out as. A- physical and different. b- physical and same. C-chemical and different. D chemical and same

Answers

The answer is C. When an object undergoes a physical change, its properties are different.

Identify the heterogeneous mixtures.
Group of answer choices

salad

water

vegetable soup

apple juice

trail mix

brass

Answers

One thing to remember is homo=same/pure and hetero=different

so heterogeneous mixture is would be salad, vegetable soup, trail mix and brass.

this is because salad, vegetable soup, trail mix, and brass have a lot components and they’re not pure.

Hopefully i could help!!

explanation of atomic radius​

Answers

Ah yes.

The atomic radius is basically the distance between the nucleus of the atom and the outermost electron in the farthest orbital of the atom. The more bigger the atomic radius , the less powerful is the force that holds together the nucleus and its electrons.

Please help!!!
When 38 g of a metal at 92 °C is added to
43 g of water at 22°C, the temperature of the
water rises to 30°C. What is the specific heat
capacity of the metal? Assume no heat was
lost to the surroundings.

Answer in units of
J/g degrees C

Answers

The specific heat  capacity of the metal : 0.610 J/g° C  

Further explanation  

The law of conservation of energy can be applied to heat changes, i.e. the heat received/absorbed is the same as the heat released  

Q abs = Q received  

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

∆T = T(final temp) - T(initial temp)

mass of metal = 38 g

T initial metal = 92 °C

mass of water = 43 g

T final water = 30  °C

T initial water = 22°C

c water = 4.18 J/g° C  

Heat absorbed by water

[tex]\tt Q=m.c.\Delta T\\\\Q=43\times 4.18\times (30-22^oC)\\\\Q=1437.92~J[/tex]

the specific heat  capacity of the metal

Q water = Q metal

[tex]\tt 1437.92=38\times c\times (92-30)\\\\c=0.610~J/g^oC[/tex]

Planets A and B are both the same size, but planet B has three times the mass of planet A. How does the weight of an object compare on the two planets?

Choose the correct answer.


The weight of an object is the same on both planets.

The weight of an object is three times larger on planet A.

The weight of an object is three times larger on planet B.

The weight of an object will depend on more factors than just the weight and size of the planet.

Answers

Answer:

The answer is d

Explanation:

Chloe is training for her first half-marathon, which requires her to run 21.1 km. Before she runs, she carefully chooses the foods that will give her the energy her body requires for the race. She stands still at the starting line, then she starts running, her body warming up as she runs. Which three energy transformations take place in this example? Potential energy to kinetic energy Chemical energy to thermal energy Chemical energy to kinetic energy Mechanical energy to chemical energy

Answers

Answer:

The transformation is of chemical energy (use the ATP molecule as a resource) which is then transformed into mechanical energy (muscle contraction) and finally transformed into thermal energy (increase in body temperature, or sweating)

Explanation:

Energy is never lost, it is always transformed, that is why energy is yielding electronic movement and expressing itself in different ways, first as chemical energy, then as mechanical energy, and lastly as thermal energy.

It is important to clarify that the energy source of all this transformation is food and energy reserves.

Is burning the glass plate is physical or chemical change?

Answers

This is a physical change because you are burning the glass plate and that changes the plate. I hope this helps. HAVE A GREAT DAY
This is a chemical reaction because stour adding heat, you are chemically doing something, physical is when you point out the obvious using your five senses. Touching it to feel how soft on object is, or what colour (vision). You are adding heat which is chemical.

how many picoliters are in 3.16 mL

Answers

Answer:

3.16×10⁹ pL

Explanation:

Given data:

Volume in mL = 3.16

Volume in picoliters = ?

Solution:

Picoliter and milliliters are units of volume. Milliliter is greater unit than picoliter.

1 mL = 10⁹ pL

Now we will convert the 3.16 mL into pL.

3.16 mL × 10⁹ pL/ 1 mL

3.16×10⁹ pL

Enter the symbol of the element which would have 36 electrons and -3 charge.

Answers

Answer:

Arsenic if I understood correctly

Explanation:

Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. Therefore, the element with atomic number 33 and -3 charge is Arsenic.

What is Ions?

Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.

Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state. The element with atomic number 33 and -3 charge is Arsenic.

Therefore, the element with atomic number 33 and -3 charge is Arsenic.

To learn more about ions, here:

https://brainly.com/question/13692734

#SPJ2

What is the mass, in grams, of 0.450 moles of Sb?

Answers

Answer:

54.9 g

Explanation:

0.450 mol x 122g/mol

Relative and average atomic mass both describe properties of an element related to its different isotopes. Out of these two Relative atomic mas is more accurate. Therefore, 54.9 g is the mass in grams of 0.450 moles of Sb.

What is mass?

Mass defines the quantity of a substance. It is measured in gram or kilogram. Average mass is the mass of atoms of an element that are isotopes. It can be calculated by multiplying mass of a isotope to natural abundance of that isotope.

Average atomic mass = (mass of first isotope× percent abundance of first isotope)+(mass of second isotope× percent abundance of second isotope)

Mass of  Sb= number of moles of  Sb ×Molar mass of  Sb

=0.450 mol x 122g/mol

=54.9 g

Therefore, 54.9 g  is the mass in grams of 0.450 moles of Sb.

To learn more about mass, here:

https://brainly.com/question/28704035

#SPJ6

If an animal is placed into a sealed container for a short time, the oxygen level will
A. decrease and the carbon dioxide level will increase.
B. decrease and the carbon dioxide level will decrease,
C, increase and the carbon dioxide level will increase.
D. decrease and the carbon dioxide level will stay the same.
E increase and the carbon dioxide level will decrease.

Answers

Answer:

A

Explanation:

Animals take in oxygen and convert it into carbon dioxide therefore the oxygen levels will decrease and the carbon dioxide levels will increase

If an animal is placed into a sealed container for a short time, the oxygen level will:  decrease and the carbon dioxide level will increase.

What happens to oxygen level inside a container:

The oxygen held inside the space is quickly being consumed by the freight or because of rusting inside a space, and that encased spaces must consistently be treated as perilous. And the carbon dioxide levels on the other hand will increase.

It will not take a long time for an animal to survive under these conditions.

Thus. option A is correct.

Find more information about Oxygen here:

brainly.com/question/26073928

Other Questions
(5x+2x^2-3)-(6+x^2-8x) A sample of an ideal gas has a volume of 2.23 L at 289 K and 1.05 atm. Calculate the pressure when the volume is 1.08 L and the temperature is 304 K. P= atm which fungi has single cell What is homeostasis (full explanation no copy right plz) if the sides of a rectangle are 12 and 15, then the diagonal is Murry Wilson, father to Brian, Dennis and Carl, managed the Beach Boys only until he was ousted in 1964? 20 POINTS AND BRAINLIEST What is the value of x in this equation?6x - 4(x - 9) = 2(3 - x)Enter your response here:Only 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ., -, and / are allowed in your answer.Answers that are mixed numbers must be entered as an improper fraction or a decimal. please help asap i will mark brainliest Help I gave u brainliest if you show me.. 11. In nineteenth century America, why did people often develop a stronger allegiance to their state orregion than the nation as a whole? What is the midpoint of the line segment with endpoints at (-6, 3) and (-10, 7)?A(-8,5)B(-16, 10)C (2,-2)D (4,-4)Choose David is completing a word list with words from this paragraph.We enjoyed all types of travel during our family vacation to Italy. First we took a train to get into the city. Later we rented bikes to explore the mountain trails. Finally, we enjoyed floating along the water in a real Italian gondola! A 4-column table with 3 rows. Column 1 is labeled Word with entries train, bike, gondola. Column 2 is labeled Part of speech with entries noun, noun, noun. Column 2 is labeled Example sentence with entries "First we took a train to get into the city," "Later we rented bikes to explore the mountain trails," "Finally, we enjoyed floating along the water in a real Italian gondola!" Column 4 is labeled Meaning with entries a rolling group of cars, a two-wheeled vehicle, blank.What is the meaning of the word gondola?a three-wheeled vehiclea long, narrow boatan extra-long busan underground train Answer the following questions in Spanish using complete sentences. 1. Nombra 3 comidas tradicionales mexicanas. Name 3 traditional Mexican foods.Tres comidas tradicionales de mexico son ______, _______, y _______.2. Cuales das festivos celebra Mxico? What festivities does Mxico celebrate?Algunos de los das festivos que Mxico celebra son.....3. Que es lo que ms te gusta de Mexico? What do you like most about Mxico?Lo que ms me gusta de Mxico es........4. Que lugar de Mxico te gustara visitar y porque?Me gustara visitar.......... porque..........5. Donde esta ubicado el pas? Where is the country located?El pais esta ubicado en.......6. Porque crees que Mxico y Estados Unidos tienen tradiciones similares? Why do you think Mxico and the United States have similar traditions?Yo creo que Mxico y Estados Unidos tienen tradiciones similares porque..... spain supported the American Revolution but France did not.true or false simply the following (z) The smallest form of matter that still retains the properties of an element Find the measure of the "?" or "X". Explain or show your What areas effect the development of human being?A. SocietyB. TribeC. Community D. All of above Are police officers bad? Which social/economic system is pictured above?