How are elliptical galaxies different from spiral galaxies?
a. They contain older stars and less gas and dust.
b. They contain younger stars and more gas and dust.
c. They are bigger than spiral galaxies.
d. They are smaller than spiral galaxies.
Answer:
A. They contain older stars and less gas and dust.
Explanation:
There are three types of galaxies:
elliptical galaxiesspiral galaxieslenticular galaxiesElliptical galaxies are galaxies shaped like an ellipse, while spiral galaxies consist of a flat, rotating disk that contains stars, gas, and dust, and a central concentration of stars called the bulge.
The difference between elliptical and spiral galaxies is in the amount of gas and dust they contain. Spiral galaxies contain large amounts of gas and dust, which means that new stars are born very often. This makes them brighter than relatively dim elliptical galaxies, which contain less gas and dust. This is why fewer new and brighter stars are born in elliptical galaxies, leaving them with older, dimmer stars.
When does nuclear fusion start during the life of a star?
Answer:
Try searching this on google
Explanation:
I might have an answer but I am not entirely sure sorry I really tried to help but there is also an app called socractic it also helps with questions
Once the temperature reaches 15,000,000 levels Celsius, nuclear fusion takes location in the center, or core, of the cloud. The high-quality heat given off by means of the nuclear fusion technique motives the gasoline to glow creating a protostar. This is the first step in the evolution of a star.
Here is a model of the sun earth system at a certain point in earths orbit around the sun based on the model which statement best explains my point is is experiencing summer
Answer:
the earth is tilted towards the sun
Explanation:
In the context, there is a sun and earth system and at a certain point when the earth is moving in its orbit around he sun, some point on the earth experiences the summers season. This is because at this point of the earths revolution, the point on the earth is facing the sun and is also tilted towards the sun. So at this point the sun rays fall directly at the surface. While the place which is tilted away from the sun, experiences winter season.
Answer:
Earth's northern hemisphere is tilted toward the Sun.
A piece of silver is heated and added to a styrofoam cup calorimeter containing 26.0 mL (the density of water is 1 g/mL) of water at 19 oC. The water reaches a maximum temperature of 44 oC after the metal was added. If the specific heat of the silver is 0.240 J/g oC and it started at 93.8 oC
Answer:
m(Ag) = 227.5g
Explanation:
...what is the mass of the piece of silver?
The heat given for the piece of silver is the same heat that is absorbed for the water, that is:
m(Ag)×C(Ag)×ΔT(Ag) = m(Water)×C(Water)×ΔT(Water)
m is mass of water in solution: 26.0mL = 26g of water
And m(Ag) is the mass of Ag, our incognite.
C is specific heat (0.240J/g°C for Ag), and 4.184J/g°C for water
ΔT is change in temperature (93.8°C - 44°C = 49.8°C) for Ag ad (44°C - 19°C = 25°C)
Replacing:
m(Ag)×C(Ag)×ΔT(Ag) = m(Water)×C(Water)×ΔT(Water)
m(Ag)×0.240J/g°C×49.8°C = 26g×4.184J/g°C×25°C
m(Ag)* 11.952J/g = 2719.6J
m(Ag) = 227.5g
which of the following lists show the elements in order, from those having the least protons to those having the most protons in the atoms?
A. K, Mg, N, O
B. C, Al, P, Cl
C. Li, Be, H, He
D. Na, Ne, He, H
The elements that have least protons to those having the most protons in the atoms are:
B. C, Al, P, Cl
Protons in an atom:There is an equal number of protons and electrons in an atom. So when moving across a period in a periodic table the number of electrons increases which also shows the increases in a number of protons. So as the atomic number increases, the number of protons and electrons also increases.
Thus, the order of elements having least to greatest protons are:
C, Al, P, Cl
C has 6 atomic number, Aluminium has 13 atomic number , Phosphorus has 14 atomic number and atomic number of chlorine is 17.
Thus, option B is correct.
Find more information about Atomic number here:
brainly.com/question/1805828
List the following particles in size order, from biggest to smallest?
A Molecules, electrons, atoms incorrect answer
B Atoms, molecules, electrons incorrect answer
C Electrons, atoms, molecules incorrect answer
D Molecules, atoms, electrons
Answer:
D. Molecules, atoms, electrons.
Explanation:
I did a quiz on this and got it right
Answer:
D. Molecules, atoms, electrons.
Explanation:
i did the test trust i got it right
Select all that apply. Choose the chemical formulas that are matched with their
correct name.
MgF2, magnesium (II) fluoride
BeO, beryllium oxide
NaCl, sodium chloride
AlF3, aluminum trifluoride
CaCl2, calcium chloride
Answer:
i think just these
NaCl
CaCl2
The movement of air caused by differences in air pressure is __________________.
Answer:
wind
Explanation:
it would be naturally caused by the pressure
Answer:
temperature or pressure differences
Explanation:
please help it’s due today
What is the mass of 1.794 mol Ba(NO3)2?
Explanation:
Molar mass of Ba(NO3)2 = 261.3368 g/mol
Why are molecular covalent compounds insoluble in water?
Answer:
Hope this will help.......
Explanation Covalent bonds are insoluble in water (H2O) , but covalent compounds are. This is because some organic compounds (covalent) contain the polar −OH group which can bond to a hydrogen ion to form water.
Which of the following is TRUE about when two atoms form a bond? a. Repulsion is greater than attraction b. Neither atoms will have a full valence shell c. Potential energy is at a minimum
Answer:
b: Neither atoms will have a full valence shell
Explanation:
I think sooo
Which of the following set of atoms has the largest electronegativity difference?
a. H and P
b. N and C
c. Li and O
d. Cl and Ca
Answer:
C
Explanation:
Li has an electronegativity of 0.98, O has an electronegativity of 3.44. 3.44-0.98= 2.46 electronegativity differnece :)
I need someones help
Answer:
y or z one of those two i think its z but im so sorry if im wrong if not z then try y also I learned this last year.
aluminum oxide is an ionic substance with formula al2o3. explain what this formula means.
Answer:
the 2 means there are 2 al and the 3 means there are 3 o
Explanation:
I hope this helps
A 2.9 kg model rocket accelerates at 15.3 m/s2 with a force of 44 N. Before launch, the model rocket was not moving. After the solid rocket engine ignited, hot gases were pushed out from the rocket engine nozzle and propelled the rocket toward the sky.
Which of Newton’s laws apply in this example? Check all that apply.
Answer:
newton's firts law
Explanation:
because it states that everybody continue its state in rest unless an external force is appy to change its state from rest to motion.
Answer:
A, B, C
Explanation:
what is polling in chemistry?
Answer:
Polling is a method used for the purification of copper or tin which contains oxide impurities
Answer:
Polling is used for the purification of copper or tin which contains oxide impurities. The impure metal is melted and stirred with green logs of wood. The heat of molten metal makes the green logs to liberate hydrocarbon gases which in turn reduce the metal oxide into metal.
How do you separate a mixture?
Answer:
We can seperate a mixture by various methods
Explanation:
Distillation, Evaporation, filtration and chromatography
What is the best explanation of an organelle?
An organelle is a structure within the cytoplasm of a eukaryotic cell that is enclosed within a membrane and performs a specific job. Although ribosomes are not enclosed within a membrane, they are still commonly referred to as organelles in eukaryotic cells.
Answer: A organelle is a structure within the cytoplasm of a eukaryotic cell that is enclosed within a membrane and performs a specific job and although ribosomes are not enclosed within a membrane, they are still commonly referred to as organelles in eukaryotic cells.
how to write the ionic formula for the K1+, MnO41- pair of ions
Answer:
Ionic formula: KMnO4
Explanation:
Pottasium permanganate (KMnO4) is an ionic compound that contains a combination of pottasium cations (K+) and permanganate anion (MnO4-). The pair of ions that make up the ionic compound cancel out each other to make it neutral.
K+ (aq) + MnO4- (aq) → KMnO4 (aq)
MnO4- contains 1 atom of manganese with a (+7) charge and four atoms of oxygen with a (-2) charge each. This forms a +7 for Mn and -8 for O4, hence, a net total of -1.
2 The substance has a mass of 0.50 kg.
34 000 J of energy is transferred to the substance to completely melt it.
The temperature of the substance does not change during this time.
Calculate the specific latent heat of fusion of the substance.
Use an equation from the Equations List.
Answer:
68000J/kg
Explanation:
Given parameters:
Mass of the substance = 0.5kg
Quantity of heat transferred to the body = 34000J
Unknown:
Specific latent heat of fusion = ?
Solution:
The specific latent heat is usually involve in phase changes;
H = mL
H is the quantity of heat supplied
m is the mass
L is the specific latent heat
Insert the parameters and solve;
34000 = 0.5 x L
L = [tex]\frac{34000}{0.5}[/tex] = 68000J/kg
How is a "decay event' recorded
Which of the following best defines a basic solution?
¿Por qué un trozo de sal común es frágil y se puede romper fácilmente cuando se le somete a una fuerza y no ocurre lo mismo con un trozo de metal que se deforma antes de romperse?
Answer:
Explanation:
La sal común es un compuesto iónico, es decir que sus átomos (Na y Cl) están unidos entre sí por fuerzas electrostáticas, y el metal está unido entre sí por uniones metálicas. La naturaleza de estas uniones es diferente y en base a las fuerzas de atracción que hay entre los átomos en compuestos con este tipo de uniones, la propiedades físicas generales serán diferentes.
En el caso de los metales, los átomos metálicos están colocados unos sobre otros de forma ordenada, pero no fijamente retenida, y los electrones de valencia están delocalizados a través de todo el cristal metálico. Por esta razón, cuando se le aplica una fuerza a un metal, estos átomos pueden deslizarse unos sobre otros. Ésta es la propiedad que le da a los metales su maleabilidad.
En el caso de los compuestos iónicos, los aniones y cationes que lo componen están ordenados en el cristal de una forma más rígida y por eso cuando se les aplica una fuerza éstos compuestos se rompen mucho más fácil, ya que no pueden deformarse.
melting is considered a(n) ___ change because energy is gained by the substance as it changes state
A. Physical.
B. Chemical.
C. Volume.
D. Dynamic.
The chemical equation represents a reaction between ammonia and oxygen to form nitrogen monoxide and water. 4 N H 3 ( g ) + 5 O 2 ( g ) → 4 NO ( g ) + 6 H 2 O ( g ) What is the limiting reagent when a 4.50 g sample of ammonia is mixed with 15.80 g of oxygen?
The limiting reagent : NH₃
Further explanationA method that can be used to find limiting reactants is to divide the number of moles of known substances by their respective coefficients, and small or exhausted reactants become a limiting reactant
Reaction
4NH₃(g)+5O₂(g)⇒4NO(g)+6H₂O(g)
mol NH₃ :
[tex]\tt \dfrac{4.5}{17}=0.265[/tex]
mol O₂ :
[tex]\tt \dfrac{15.8}{32}=0.494[/tex]
mol ratio
NH₃ :
[tex]\tt \dfrac{0.265}{4}=0.06625[/tex]
O₂ :
[tex]\tt \dfrac{0.494}{5}=0.0988[/tex]
Limiting reactants : NH₃ (smaller ratio)
The limiting reagent when a 4.50 g sample of ammonia is mixed with 15.80 g of oxygen is NH₃
Calculation of limiting reagent:The limiting reactant refers to the reactant that gets consumed first in a chemical reaction and thus it limits how much product can be created or developed. A method that can be used to determine limiting reactants that to divide the number of moles by their respective coefficients.
So,
For mol NH₃ :
[tex]= 4.5\div 17[/tex]
= 0.494
For mol O₂ :
[tex]= 15.8 \div 32[/tex]
= 0.494
For mol ratio
NH₃ :
[tex]= 0.265 \div 4[/tex]
= 0.06625
O₂ :
[tex]= 0.494 \div 5[/tex]
= 0.0988
Based on the above calculations we can say that it is NH₃
learn more about the oxygen here: https://brainly.com/question/19803828
What are the advantages of using resources such as geothermal energy, solar energy, and hydropower?
They produce large amounts of energy from burning fuels.
They can generate power by burning wastes.
They come from energy sources that never run out.
They increase the amount of greenhouse gasses.
WILL MARK YOU BRAINLEIST What do sound waves need to have to travel from one place to another?
What do sound waves need to have to travel from one place to another?
Question 5 options:
steel
water
air
a medium
Answer:
a medium!!!!
Explanation:
ITS CORRECT!!!! I GOT IT RIGHT ON MY TESTTTTT! I PROMISEEE
Help pleasee I need help to write the formulas i’m so lost
Answer:
NH4
Explanation:
What sport was used to demonstrate Newton's 3 Laws?