Number of Br atoms : 2.679 x 10²³
Further explanationThe mole is the number of particles contained in a substance
1 mol = 6.02.10²³
Moles can also be determined from the amount of substance mass and its molar mass
[tex]\tt mol=\dfrac{mass}{MW}[/tex]
Proust stated the Comparative Law that compounds are formed from elements with the same Mass Comparison so that the compound has a fixed composition of elements
mass of Br in CH₂Br₂[tex]\tt mass~Br=\dfrac{2.Ar~Br}{MW~CH_2Br_2}\times mass~CH_2Br_2\\\\mass~Br=\dfrac{2.80}{174}\times 38.7=35.59~g[/tex]
mol of Br[tex]\tt \dfrac{35.59}{80}=0.445[/tex]
number of atoms[tex]\tt 0.445\times 6.02\times 10^{23}=\boxed{\bold{2.679\times 10^{23}}}[/tex]
Which pair of elements will have the same number of valence numbers
A- lithium and barium
B- gallium and germanium
C- tellurium and polonium
D- iondine and xenon
Mark as brainlist :)
Is 5O2 a Element or Compound?
2
A train travels 25 km in 0.5 hrs. How fast is the train going?
Answer:
15
Explanation:
Answer:
50 km/h
Explanation:
Since in half an hour it has gone 25km, double that (25 x 2) and you get your answer in km/h. Therefore, the train is going 50km/h.
What is the process by which new oceanic crust is added?
A Seafloor Spreading
B) Earthquakes
C) Trenches
D) Plate Tectonics
Answer: A
Explanation:
Answer:
A.Seafloor spreading
Explanation:
How many elements make up Sodium Bicarbonate?
please answer its due in 10 minutes teacher just assigned it 5 minutes ago
Answer:
please upload a clearer picture
Answer:
1 Rain falling down
2)Freezing 3)Melting 4)Adding or removing energy from matter causes a physical change as matter moves from ome place to the other5)5heWhat is the role of
electrons within an
atom?
A.
Electrons are in the nucleus and have a
negative charge
B. Electrons are in the nucleus and have a
positive charge
C. Electrons are outside the nucleus and
have a negative charge
D. Electrons are outside the nucleus and
have a positive charge
Option C - Electrons are outside the nucleus and and have a negative charge is the correct alternative.
We have electrons.
We have to determine their role inside the atom.
What are Electrons ?An electron is one of the subatomic particles within an atom. It is negatively charged particle whose magnitude is 1.6 x 10⁻¹⁹ C.
According to the question -
The role of electrons inside the atom is as follows -
Electrons revolve around the nucleus.They carry a negative - charge of -1.6 x 10⁻¹⁹ C.Hence, Option C is the correct alternative.
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someone please i need help
Answer:
the answer 32/43
Explanation:
The rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three. Remember that proportionality is a constant relationship or ratio between different magnitudes.
If the relationship between the magnitudes is direct, that is, when one magnitude increases, so does the other, the direct rule of three must be applied. To solve a direct rule of three, the following formula must be followed:
a ⇒ b
c ⇒ x
So,
The direct rule of three is the rule applied in this case as follows: If the change in water level is 0.05 inches per hour, what is the change in water level after 24 hours?
change in water level=1.2 inches
To pass a decimal number to a fraction, you must:
Put the decimal number in a fraction above a 1. That is, the decimal number is the numerator, 1 the denominator.
Find an equivalent fraction. That fraction will carry in the denominator a 1, an
Finally, the change in the water level of the pond after 24 hours is 1.2 inches or what is the same inches
What kind of reaction happens when two compounds switch elements? Apex
Answer:
A replacement reaction occurs when elements switch places in compounds. This type of reaction involves ions. Generally, more reactive elements replace less reactive elements. A single replacement reaction occurs when one element replaces another element in one compound.
Explanation:
Just figured it out!
Answer: a double - replacement reaction
Explanation:
I just got it right on Apex
Which tools can be used to measure the volume of a substance? Select the two correct answers.
a. tape measure
b. digital balance
c. measuring cup
d. graduated cylinder
Answer:
graduated cylinder and a scale can be used to measure the volume of a substance. hope this is helpful
Explanation:
How do the rock cycle and the carbon cycle relate to each other?
Answer:
Through a series of chemical reactions and tectonic activity, carbon takes between 100-200 million years to move between rocks, soil, ocean, and atmosphere in the slow carbon cycle. ... The acid dissolves rocks—a process called chemical weathering—and releases calcium, magnesium, potassium, or sodium ions.
Use a sentence to describe how the mantle moves. Use another sentence to describe why the mantle moves this way.
Answer:
Correct distribution of your weight and shifting of your center of gravity are crucial for the mantling technique to...
Bring your foot as high as you can, preferably planting down the heel.
Free up your arms so that you can rotate your hand and push down with your palm.
Remember to chalk up.
How could the combustibility of a substance influence how the substance is used?
Answer:
Combustibility is a measure of how easily a substance bursts into flame, through fire or combustion. This is an important property to consider when a substance is used for construction or is being stored. It is also important in processes that produce combustible substances as by product
Which element would you expect to have the largest radius based on the Periodic Table?
Lead
Selenium
Chlorine
Answer:
Lead
Explanation:
As you move down the periodic table, the elements get larger and gain additional electron shells, increasing the radius. In order, they are on the table as Chlorine, Selenium, Lead.
Which metal is most likely to form more than one kind of positively charged ion?
A.Sodium
B.Barium
C.Nickel
D.Magnesium
Answer:
D.Magnesium
Explanation:
Cause imma nerd
3. What is a molecule?
Answer:
a molecule is defined as an element or compound consisting of two or more atoms held together by chemical bonds
i hope this helps :)
Explanation:
Question 1 (4 points)
Which of the following is/are true about Van der Waals forces?
A. They are very weak
B. They are a a type of momentary dipole
C. Both 1 and 2 are correct
D. neither 1 nor 2 is correct
Answer:
C. Both 1 and 2 are correct.
What is true about warm, saturated air?
It contains less water vapor than cold air.
It contains the same amount of water vapor as cold air.
It does not contain any water vapor.
It contains more water vapor than cold air.
Answer:
It contains more water vapor than cold air
According to the process of conduction which take place from hot to cold end warm saturated air has more water vapor than cold air.
Conduction is defined as a process as a means of which heat is transferred from the hotter end of the body to it's cooler end.Heat flows spontaneously from a body which is hot to a body which is cold.
In the process of conduction,heat flow is within the body and through itself.In solids the conduction of heat is due to the vibrations and collisions of molecules while in liquids and gases it is due to the random motion of the molecules .
As per the concept of conduction, warm hair has more water vapor than cold air, thus the correct option is that warm, saturated air has more water vapor than cold air.
Learn more about conduction,here:
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What is a Testable question I can use for tennis balls
Answer:
How long does it take for a tennis ball to fall from a certain height if recorded in different weather?
Explanation:
Can I have brainliest?
Answer:
How far can a ball travel if thrown during different wind speed?
Explanation:
Brainliest Plzzz!!!
The unit for force is kg m/s.
True Or false?
when water changes state from a liquid to a solid is energy absorbed or lost?
Answer:
Loses
Explanation:
liquid changes into solid, heat is released. The energy released upon freezing, known as the enthalpy of fusion, is a latent heat, and is exactly the same as the energy required to melt the same amount of the solid.
Answer:
Matter either loses or absorbs energy when it changes from one state to another. For example, when matter changes from a liquid to a solid, it loses energy. The opposite happens when matter changes from a solid to a liquid. For a solid to change to a liquid, matter must absorb energy from its surroundings.
Explanation:
Which formula is an ionic compound?
A.NaF
B.N2
C.NO2
D.CO2
FIRST ACCUAL ANSWER GETS BRAINLIST :)
Answer:
NaF
Explanation:
Answer: the answer is Naf
Explanation
and I love pop tart kitties OWO but i hope this helped i have a in science so i got 100% on it bye bye OWO
Is the solution a heterogeneous mixture?
Answer:
nope homogeneous
Explanation:
hope this helps :)
Answer:
SOLUTIONS are homogeneous mixtures. A solution is a mixture of two or more substances in a single phase.
Calculate the maximum mass of potassium sulfate, K2SO4, that could be formed when 4.9 g of sulfuric acid reacts with excess potassium hydroxide.
H2SO4 + 2KOH → K2SO4 + 2H2O
Answer:
From 4.9 g of sulfuric acid 8.175 g of potassium sulfate is formed.
Explanation:
Given data:
Mass of H₂SO₄ = 4.9 g
Mass of K₂SO₄ formed = ?
Solution:
Chemical reaction:
H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O
Number of moles of H₂SO₄:
Number of moles = mass/ molar mass
Number of moles = 4.9 g/ 98.1 g/mol
Number of moles = 0.05 mol
Now we will compare the moles of H₂SO₄ with K₂SO₄ .
H₂SO₄ : K₂SO₄
1 : 1
0.05 : 0.05
Mass of K₂SO₄:
Mass = number of moles × molar mass
Mass = 0.05 mol × 174.3 g/mol
Mass = 8.715 g
Thus, from 4.9 g of sulfuric acid 8.175 g of potassium sulfate is formed.
Help please if you can answer this first I'll give you the brainliest
Answer:
1. gas
2. false
Explanation:
How does an increase in thermal energy influence the particles of the reactants in a chemical reaction?
Group of answer choices
it increases the chance of particles being properly aligned by increasing the number of collisions
it decreases the number of particle collisions
it increases the number of collisions by speeding up the particle motion
Answer:
the last one it increases number of collisions by speeding up the particle motion
Explanation:
the more thermal energy something it has the faster particles move
the action force always acts in the ____ direction as the reaction force
Answer:
opposite
Explanation:
Newtons law explains that for every action force there is an equal and opposite reaction.
What is the charge of an Pb atom with 81 electrons?
Answer:
+1 Because there are 82 protons.
Explanation:
A meteorologist uses a weather map to explain an upcoming change in weather. The map shows a blue line with triangles approaching a red line with semicircles. Based on the map, which weather prediction is most valid? (1 point) A a significant drop in temperature will occur across the area. B There is no chance of precipitation in the forecast. C Warm temperatures will replace cold temperatures. D Humidity levels will rise.
Answer:
Option C: Warm temperatures will replace cold temperatures.
Explanation:
In a weather map, a warm front is depicted with a red line and red semi circles while a cold front is depicted with a blue line and blue triangles.
Now, we are told that the map shows a blue line with triangles approaching a red line with semi-circles. This means that the cold front is approaching the warm front.
Now a warm front is simply defined as the transition zone where warm air mass gradually replaces a cold air.
Thus, it means the weather map depicts the fact that warm temperature is replacing cold temperature.
Thus; Option C is correct.
Answer: 1: A cold front moved into the area. 2: It would actually be A. A significant drop in temperature will occur across the area. 3: Movement of large air masses. 4: “A Strong Cold Front Threatens the Region”. 5: a meeting of two air masses with major differences in temperature and moisture.
Hope you got 100 because of this!
Help fast I have a few left
Answer: A
Explanation: 0.00624 x 10^8
All you have to do is move the . 8 units left
This gives you 624000.0