Answer:
130.68 × 10²³ atoms
Explanation:
Given data:
Number of moles of Rn = 21.7 mol
Number of atoms = ?
Solution:
Avogadro number:
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
21.7 mol × 6.022 × 10²³ atoms / 1mol
130.68 × 10²³ atoms
Need help!!! Also don't joke around please
If predators A and B prey upon the same species and predator A is eliminated, the population of predator B will likely __________. a. be eliminated b. increase c. decrease d. remain the same Please select the best answer from the choices provided A B C D
Answer: B. Increase because there will be more resources for the remaining predators
Answer: B
Explanation: YES
can someone please answer this? there’s two answers and it’s due in 10 minutes
Use the portion of the periodic table shown below to answer the questions
sodium
11
magnesium
12
Na Mg
22930
potasiun
19
24305
cloum
20
21
K
Ca
SC
39.00
rubidium
37
Rb
25408
40.078
strontium
38
44.956
yorum
39
Sr
Y
87.62
88. SOS
Part 1: Name two elements that have the same properties as potassium (K). (4 points)
Part 2: Determine the number of protons, electrons, and neutrons present in an atom of magnesium (Mg). Explain how you determined your answer using complete sentences. (6
points)
Answer:
Part 1:sodium
rubidium
Part 2: protons neutrons and electrons are all 12
The number of protons is equal to the no. of neutrons from the electronic arrangement of magnesium and the no. of electrons is got from the atomic no. of magnesium
24. All elements found on the left side of the Periodic Table of
the Elements have what properties in common?
Answer:
have one delocalised electron
Explanation:
The elements which are present of left side of periodic table have similar chemical properties.
What is periodic table?Periodic table is a tabular arrangement of elements wherein elements are arranged according to their atomic numbers. It consists of seven horizontal rows called periods and eighteen vertical columns called groups .
Elements in the same group have similar chemical properties as they have same number of valence electrons. While, electrons in the same period have different valence electrons as electrons are added to same shell and hence have a little variation in chemical properties.
It is called periodic as properties repeat after an interval of certain electronic configuration. Elements are divided in four blocks depending on their properties.
Learn more about periodic table ,here:
https://brainly.com/question/11155928
#SPJ2
An element containing a charge.
Answer:
That means an atom with a neutral charge is one where the number of electrons is equal to the atomic number. Ions are atoms with extra electrons or missing electrons. When you are missing an electron or two, you have a positive charge. When you have an extra electron or two, you have a negative charge
Answer: The Charge of Elements
For example, sodium is an element with 11 protons within the nucleus and 11 electrons. Another example of an element is carbon, which has six protons within the nucleus and six electrons. In both cases, these elements have a neutral charge.
Explanation: That means an atom with a neutral charge is one where the number of electrons is equal to the atomic number. Ions are atoms with extra electrons or missing electrons. When you are missing an electron or two, you have a positive charge. When you have an extra electron or two, you have a negative charge.
ions of an element (elements with different charges) contain different numbers of what
Answer:
an ion is an element that has different numbers of protons and electrons
Explanation:
An ion is positive when it has more protons than electrons and negative when it has more electrons than ions.
(Hope this was helpful!) :)
A spring running horizontally has areas with the coils closer together and areas with them farther apart. A label A points to areas where they are closer together. A label B points to areas where they are farther apart. A label C sits near a bracket connecting the center of two successive areas with the coils farther apart, which are separated by an area of closer coils. Label the parts of the longitudinal wave. Compressions: Rarefactions: Wavelength:
Answer: A,B,C
Explanation:
Answer:
a
b
c
Explanation:
edge
Few terrestrial animals can survive in the Arctic region. Most of them need a thick coat of fur or fat to survive. Based on this information, which factor seems to primarily affect animals life in this biome?
A. Rainfall
B. Salinity
C. Soil depth
D. Sunlight
E. Temperature
if 42 grams of carbon in 52 grams of oxygen are used how many grams of CO2 will be produced. I need to show work.
C+ O2 --> CO2
Answer:
How many moles of oxygen gas are required to make 8.33 moles of carbon dioxide? ... be used to produce 1.99 grams of water. 1.99 mg H2O X. 1mol H2O. 18.0g X ... c. If the reaction produces 5.3 mg of carbon dioxide how many grams of water ... X. 25mol O2. 2mol C8H18. X. 32.0g O2. 1mol O2. = 4.80 x 103g O2. Answer ...
Explanation:
Which of the following is not an organic compound?
C 6H 14
CO 2
CH 4
C 12H 22O 11
Answer:
CO2 I believe
Explanation:
It doesn't have any hydrogen
5) If I have 20 liters of gas at a temperature of 67 °C and a pressure of 88.89 atm, what will
be the pressure of the gas if I raise the temperature to 94 °C and decrease the volume to 12
liters?
6) I have an unknown volume of gas at a pressure of 0.50 atm and a temperature of 325 K.
If I raise the pressure to 900 torr, decrease the temperature to 320 K, and measure the final
volume to be 48 liters, what was the initial volume of the gas?
7) If I have 21 liters of gas held at a pressure of 78 atm and a temperature of 800 K, what
will be the volume of the gas if I decrease the pressure to 45 atm and decrease the temperature
to 750 K?
8) If I have 3.9 L of gas at a pressure of 5.0 atm and a temperature of 50.0°C, what will be
the temperature of the gas if I decrease the volume of the gas to 2.4 L and decrease the
pressure to 303.0 kPa?
9) I have an unknown volume of gas held at a temperature of 115 K in a container with a
pressure of 60.0 atm. If by increasing the temperature to 225 K and decreasing the pressure to
30.0 atm causes the volume of the gas to be 25 liters, how many liters of gas did I start with?
work too pls !! thank you so much !!!
Answer:
Explanation:
We shall use gas law as follows
P₁ V₁ / T₁ = P₂ V₂ / T₂
5 ) V₁ = 20 , P₁ = 88.89 , T₁ = 273+ 67 = 340 K .
V₂ = 12 , P₂ = ? , T₂ = 273+ 94 = 367 K .
88.89 x 20 / 340 = P₂ x 12 / 367
P₂ = 159.9 atm .
6 )
V₁ = ? , P₁ = .5 , T₁ = 325 K .
V₂ = 48 , P₂ = 900/760 = 1.184 , T₂ = 320 K .
V₁ x .5 / 325 = 48 x 1.184 / 320
V₁ = 115.44 litres .
7 )
V₁ = 21 , P₁ = 78 , T₁ = 800 K .
V₂ = ? , P₂ =45 , T₂ = 750 K .
21 x 78 / 800 = V₂ x 45 / 750
V₂ = 34.125 litres .
8 )
V₁ = 3.9 , P₁ = 5 x 10⁵ Pa , T₁ = 323 K .
V₂ = 2.4 , P₂ =3.03 x 10⁵Pa , T₂ = ? .
3.9 x 5 x 10⁵ / 323 = 2.4 x 3.03 x10⁵ / T₂
T₂ = 120.45 K
= -152.54⁰C .
9 )
V₁ = ? , P₁ = 60 , T₁ = 115 K .
V₂ = 25 , P₂ =30 , T₂ = 225.
V₁ x 60 / 115 = 25 x 30 / 225
V₁ = 6.39 litre .
A measured value for the atomic radius of platinum
atoms was determined to be 143 picometers. What is the percent error of this measured
value?
A) 0.10%
B) 9.1%
C) 10.%
D) 13%
Since the actual value of the atomic radius of platinum atoms was not given in the problem, I chose 175 pm which gives an error of 18.28%.
The actual atomic radius of platinum atoms is 175 pm
We can see from the question that the measured value of the atomic radius of platinum atoms was determined to be 143 pm.
Recall that;
Percent error = Absolute value of (measured value - actual value)/actual value * 100
Since the actual value of the atomic radius was not given, let us take it to be 175 pm for the purpose of this problem
Percent error = Absolute value of (143 - 175)/175 * 100
Percent error = 18.28%
Learn more: https://brainly.com/question/4170313
The percent error of this measured value ; ( D ) approximately 13%
The percent error of a measured value
= [ ( actual value - measured value ) / ( actual value ) ] * 100
= [ ( 175 pm - 143 pm ) / ( 175 pm ) ] * 100
= 18.29%
From the options given the closest value to the calculated value is 13%
Hence we can conclude that the percent error of this measured value is approximately 13%.
Learn more : https://brainly.com/question/2138898
Although some data related to the question is missing the actual value of the atomic radius of platinum is 175 pm
How many moles of oxygen are required for the combustion of 35.5 g of Magnesium Mg+O2-->MgO Please balance
Answer:
0.74 moles of oxygen are required for combustion
Explanation:
Given data:
Number of moles of oxygen required = ?
Mass of Mg = 35.5 g
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 35.5 g/ 24 g/mol
Number of moles = 1.48 mol
Now we will compare the moles of Mg with oxygen.
Mg : O₂
2 : 1
1.48 : 1/2×1.48 = 0.74 mol
0.74 moles of oxygen are required for combustion.
What type of volcano will most likely form when an eruption takes place with explosive force and layers of ash accumulate? I WILL GIVE MANY POINTS!!!! PROMISE!
Cinder cone volcano
Composite volcano
Crater volcano
Shield volcano
Answer:
A.) A cinder cone vocano
Explanation:
Cinder cone volcanos give off more ash, rather then an explosion, hense the name "cinder cone".
Answer:
Cinder Cone Volcano
Explanation:
Plzzz help i need the answer now
Answer:
Explanation:5,2 methyle- dhexene
Can u please answer if you know.
Answer:
plants
Explanation:
they are plant cells, happy Thanksgiving :)
Answer: photosynthetic tissues
Explanation: Chloroplasts are present in the cells of all green tissues of plants and algae. Chloroplasts are also found in photosynthetic tissues that do not appear green, such as the brown blades of giant kelp or the red leaves of certain plants.
When you stand on a bathroom scale, what force or forces are acting on you?
A) normal force only
B) gravitational force only
C) gravitational and normal forces
Answer:
B
Explanation:
Lets see here, Gravity is pulling you down but your body is repelling to gravity. Meaning that gravity is pulling down your weight and the scale is reading it.
Hope this helped!
What are the correct units of density
Metals are found on the left-hand side of the periodic table. True or False
Answer:
true pls mark brainiest
Explanation:
How does a lightning rod protect a
building from lightning damage?
Answer:
The lightning rod attracts lightning and is not connected to any other pieces of metal that may harm any electrical circuits.
Explanation:
I hope this helps, I tried my best to explain it quickly for you.
Answer/Explanation:
A lightning rod is a metal rod that is used to dislocate where lighting hits. Lightning is going to hit the closest point that it has been attracted too. So, the lightning rod was invented to attract lighting to something less potentially dangerous. Instead of hitting a building causing fires and collapsing, it takes the bolt so that nothing else has to.
If you remove one bulb from a string of lights, all the remaining lights will go out. Are the lights in a series or parallel circuit? EXPLAIN.
Answer:
series bro. i think bro
Answer:
they are in a parallel
Explanation:
this is because the string is also connected to the other bulbs
If an industrial worker knows that his chemical process is 87.3% efficient and he needs to
collect 100.0g of the product when all is said and done, what should his theoretical yield
be (in grams)?
I legitimately think it's 87.3 grams
How do you measure the volume of a rubber duck?
Answer:
Im sorry i though this was a joke i don't know I'm sorry:
[tex]\huge\boxed{Buoyant Force}[/tex]
_____________________________________ARCHEMEDIS LAW (EUREKA)A body at rest in a fluid is acted upon by a force pushing upward called the buoyant force, which is equal to the weight of the fluid that the body displaces. If the body is completely submerged, the volume of fluid displaced is equal to the volume of the body. That is how we find the Volume of the Irregularly shaped objects.
_____________________________________FUN FACT:Archemedes the GREAT GREEK PHYSICIST was in a real problem finding out the formula of how to find the volume of irregular object. After countless failures in finding it, once he was going to get a apparently "BUBBLE BATH", So when he got into the tub the water displaced and got out from the tub resulting in the splash of water. His MIND CLICKED that we could find the volume by submerging the irregular object into the measured water and then substract the displaced water from it. He ran NAKED out of the house because of the happiness saying EUREKA! EUREKA! which literally means "I have found it". Thus this law of Archemedes is also called EUREKA LAW. So to simply remember how to find volume of irregular object keep EUREKA in mind.
_____________________________________[tex]Best Regards,[/tex]
[tex]"BORZ"[/tex]What are the lowest ratio of coefficients needed to balance the equation below? __ CaCl2 + __Al --> __AlCl3 + __Ca
Tumu’s class was given an assignment to feature a scientist that contributed to the development of the cell theory. The class decided to use images to feature the scientist of their choice. Which image would Tumu most likely use in his assignment to feature Rudolf Virchow?
Answer: the way root cells reproduce to increase root length
Explanation:
Rudolf Ludwig Carl Virchowas known as the founder of social medicine and also the father of modern pathology.
Virchow posited that all cells are gotten from already existing cells and he used this in his work towards cellular pathology, as it was made clear that diseases takes place at the cellular level. He posited that the cells that are malfunctioning cause diseases.
Based on the above analysis, the image that Tumu would most likely use in his assignment to feature Rudolf Virchow is the way root cells reproduce to increase root length.
Answer:
the way root cells reproduce to increase root length
Explanation:
how many atoms are present in 9.8g of H2SO4
Answer:
Explanation:
98 gH
2
SO
4
contains1 mole of H
2
SO
4
.
1 mole of H
2
SO
4
contain=1 mole of sulphur atoms.
∴9.8 g of H
2
SO
4
contain =0.1 mol of sulphur atom.
Thus, number of sulphur-atoms =n×N
A
(in 9.8 g of H
2
SO
4
)
=0.1×6.023×10
23
=0.6023×10
23
.
Self registering thermometers:
record only the maximum and minimum temperatures they are exposed to
record only the minimum temperature they are exposed to
record only the average temperature they are exposed to
record only the maximum temperature they are exposed to
Answer:
record only the maximum and minimum temperatures they are exposed to
Answer:
ur answer would be (A)
Explanation:
Which solid below is held together by all mobile electrons being shared?
1) CS₂ 2)NaCl
3)Ni 4)Br₂
True or False?
A substance is found to be made up of more than
one atom, but the atoms are all the same. This
substance is most likely a compound.
Answer:
No.
Explanation:
Compounds are made from different atoms. As an example, CO2 is made from Carbon and Oxygen. All atoms being same would make it a pure element, and not a compound.
PLEASE GIVE BRAINLIEST
False, because the substance is most likely an element.
What are atoms?Atoms are the smallest functional or fundamental unit of any substance.
When two or more than two atoms combine, formation of molecule takes place. That molecule will called compound if two different types of atoms combined to form that, but if same number of atoms combine together then they will form an pure element.
Example of compounds are CO₂, H₂O, etc.
And example of elements are O₂, H₂, etc.
Hence, the given statement if false for the compound.
To know more about atoms, visit the below link:
https://brainly.com/question/6258301