how many moles of Si are in 78.0 grams of silicon
Answers
Answer:
[tex]\boxed {\boxed {\sf 2.78 \ mol \ Si}}}[/tex]
Explanation:
To convert from grams to moles, we must use the molar mass. This number can be found on the Periodic Table.
Si (Silicon): 28.085 g/molWe can use number as a ratio.
[tex]\frac { 28.085 \ g \ Si}{ 1 \ mol \ Si}[/tex]
Multiply by the given number of grams.
[tex]78.0 \ g \ Si *\frac { 28.085 \ g \ Si}{ 1 \ mol \ Si}[/tex]
Flip the fraction so the grams of silicon cancel.
[tex]78.0 \ g \ Si *\frac {1 \ mol \ Si }{ 28.085 \ g \ Si}[/tex]
[tex]78.0 *\frac {1 \ mol \ Si }{ 28.085 }[/tex]
[tex]\frac {78.0 \ mol \ Si }{ 28.085 }= 2.77728324729 \ mol \ Si[/tex]
The original number of grams (78.0) has 3 significant figures, so our answer must have the same. For the number of moles calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 7 to a 8.
[tex]2.78 \ mol \ Si[/tex]
There are about 2.78 moles of silicon in 78.0 grams.
Related Questions
Analyze the given diagram of the carbon cycle below.
An image of carbon cycle is shown. The sun, a cloud, two trees, one towards left and the other towards right, an animal, lake, and a factory are included. Arrow A points from the sun to the left tree. Arrow B points from the air above the clouds to the left tree. Arrow C points from the factory towards the air above the clouds. Arrow D points from the air to the lake labeled Carbonates in Water. Arrow E points from the label Dead Organism under the animal to label Fossils and Fossil Fuels. Arrow F points from the right tree to the air.
Part 1: Which process does arrow F represent?
Part 2: Explain how matter is conserved during the process.
Part 3: Justify why this process is a recycling of carbon in the carbon cycle.
Use complete sentences to explain your answer. (10 points)
Answers
Answer:
Part 1:
Arrow F represents Cellular Respiration, showing how the tree produces carbon after it has finished the process of Cellular Respiration.
Part 2:
Matter is conserved in this image because it shows the process of Photosynthesis and cellular respiration. These are both examples of The Law of Conservation of Mass. During both of these processes, the mass of the reactants is the same as the mass of the products.
Part 3:
This process shows the carbon cycle by showing how carbon transfers to many different types of matter and back again. It shows the process of cellular respiration, which produces carbon using the products of photosynthesis, which uses the carbon produced by cellular respiration. This shows a cycle because each of them depends on the other.
What is the molar ratio between carbon dioxide to water?
2 C4H10 + 13 O2 = 8 CO2 + 10 H2O
Answers
Answer:
8:10
Explanation:
The coefficients of a balanced chemical equation give us the mole ratios. The coefficient of carbon dioxide here is 8 and water is 10.
The splitting apart of an atom's nucleus is called
Fizzing
Fission
Fusion
Atomic
Answers
Answer:
it is option B
(Fission)
hope it helps
what are cells
1. the smallest things that can carry out life processes
2. parts of a molecule
3. parts of an atom
Answers
1.the smallest things that can carry out life proccess
From a cross between a short haired guinea pig (hh) and a long haired guinea pig (Hh), what would be the possible phenotypes of the offspring?
A. 100% will have long hair.
OB. 75% will have long hair; 25% will have short hair.
OC. 50% will have long hair; 50% will have short hair.
O D. 25% will have long hair; 75% will have short hair.
Answers
The element which has atomic number 17 is considered from... A. Metals B. Non-metals C. Noble gas D. No correct answer Please explain with your answer.
Answers
Answer:
B. Non-metals
Explanation:
The element with the atomic number of 17 is Cl.
Chlorine belongs to the group 7 in the periodic table. It is a non metal.
Correct option: B. Non-metals
Birds' feet change slowly over time, depending on their habitat. Ptarmigans live in snowy areas and eat pine needles, twigs, and insects. Roadrunners live in deserts and plains and eat anything they can catch. Peregrine falcons live on high perches and use their talons for grasping their prey. Mallards live near water and swim and dive for food.
What is an inherited behavior or physical change that helps an organism survive and reproduce in its environment?
A. adaptation
B. variation
C. evolution
D. species
Answers
Answer:
A
Explanation:
Please help! I don’t have a time limit, so take you’re time!
Answers
Answer:
c. They have similar chemical properties.
Explanation:
Elements in a group (column) of the periodic table will all have the same number of valence electrons. Valence electrons determine a number of an element's chemical properties, which means that elements in the same group will have similar properties. For example, the alkali metals of Group One all have one valence electron and are highly reactive.
Answer:
C they have the same electrons because they are the same organism
Given 1 cm3 = 1 mL What is the volume in cubic centimeters of a 500 ml beaker? cm3
Answers
Answer:
500 cubic centimeters of water
I need help on this question
Answers
Answer:
When a front passes over an area, it means a change in the weather. Many fronts cause weather events such as rain, thunderstorms, gusty winds, and tornadoes. At a cold front, there may be dramatic thunderstorms. At a warm front, there may be low stratus clouds. Usually, the skies clear once the front has passed.
Explanation:
Plz make me brainliest :)
Have a nice day
Answer:
Email your teacher they will give you the answers try it yourself
Explanation:
Name at least two examples of biomass energy sources
Answers
Answer:
two examples are
wood and Ethanol
HELP!! URGENT!! WILL GIVE BRAINIEST
Answers
Answer:
11. Mn (CH 3 CO 2) 2. (H 2 O) n where n = 0, 2, 4.
12. Au2O
Explanation:
Hope this helps
NH3+
H2(SO4) =
(NH4)2(SO4)
Balance
Answers
Answer:
2 NH3 + H2SO4 = (NH4)2SO4
Explanation:
The reaction type is synthesis
A sealed container at 25oC contains a gas at a pressure of 104 kPa. What is the pressure of the gas when it is heated to 225oC?
1. 304 kPa
2. 936 kPa
3. 174 kPa
4. 62.2 kPa
Answers
Answer:
174 kPa
Explanation:
Given that,
Initial temperature, T₁ = 25° C = 25+273 = 298 K
Final temperature, T₂ = 225°C = 225 + 273 = 498 K
Initial pressure, P₁ = 104 kPa
We need to find the new pressure. The relation between the temperature and pressure is given by :
[tex]\dfrac{P_1}{T_1}=\dfrac{P_2}{T_2}[/tex]
So,
[tex]P_2=\dfrac{P_1T_2}{T_1}\\\\P_2=\dfrac{104\times 498}{298}\\\\P_2=173.79\ kPa[/tex]
or
P₂ = 174 kPa
So, the new pressure is 174 kPa.
Write the product for each synthesis reaction . Balance the chemical equation . a) Be+O 2 Li+Cl 2 c) Mg+N 2 d) Al+Br 2 K+O 2
Answers
Answer:
j,
Explanation:
How do the melting and boiling points of water compare to that of other molecular compounds of similar molar mass?
Select one:
a. They are both much lower.
b. They are both about the same.
c. The melting point is much lower, while the boiling point is much higher.
d. They are both much higher.
Answers
Answer:
The answer is D.
Explanation:
The melting and boiling points of water compare to that of other molecular compounds of similar molar mass.
c. The melting point is much lower, while the boiling point is much higher.
Melting point of water:The melting point for water is 0 degrees C (32 degrees F). The boiling point of water varies with atmospheric pressure. At lower pressure or higher altitudes, the boiling point is lower. At sea level, pure water boils at 212 °F (100°C). The melting point of water is the temperature at which it changes from solid ice into liquid water.
Thus, the correct option is c.
Find more information about Melting point here:
brainly.com/question/40140
Someone please help me real quick pls :(
Acid reflux occurs when acid from a person's stomach escapes from the stomach and enters the esophagus, a flexible tube that leads into the stomach. Which substance would be best for neutralizing stomach acid?
Answers
The substance which will be the best for neutralizing stomach acid is Antacid.
What is Antacid ?Antacids are medications that counteract (neutralize) your stomach's acid to ease heartburn and indigestion.
Heartburn, indigestion, and upset stomach can be treated with antacids, which neutralize stomach acid.
Some antacids have been used to treat diarrhea and constipation. Marketed antacids include sodium, calcium, magnesium, or aluminum salts.
They are available without a prescription from pharmacies and stores and come in liquid or chewable tablet form.
Therefore, The substance which will be the best for neutralizing stomach acid is Antacid.
Learn more about Antacid here ;
https://brainly.com/question/1328376
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hello, do you think you know the order of this?
Answers
Answer:
1. A
2. B
3. D
4. C
Explanation:
Just trust me. Good luck on your test! (I go to K12 as well.)
The muscular system and the skeletal system work together so the body can do what?
move
pump blood
get oxygen
digest food
Answers
Answer:
Move
Explanation:
Which is an example of a parasite and host relationship?
Answers
Answer:
A parasitic relationship is one in which one organism, the parasite, lives off of another organism, the host, harming it and possibly causing death. The parasite lives on or in the body of the host. A few examples of parasites are tapeworms, fleas, and barnacles.
Answer:Tapeworms are a common parasite that can live in humans. They go into the digestive system and get food by eating the hosts partly digested food.
Explanation:
According to VSEPR theory, what is the bond angle of CCl4?
a. 90
b. 109.5
c. 120
d. 180
Answers
You need to make 10.0 L of 1.2 M KNO3. What molar ( concentration) would the potassium nitrate solution need to be if you were to use only 2.5 L of it? *
Answers
Answer:
2.5L [NaCl] concentrate needs to be 4.8 Molar solution before dilution to prep 10L of 1.2M KNO₃ solution.
Explanation:
Generally, moles of solute in solution before dilution must equal moles of solute after dilution.
By definition Molarity = moles solute/volume of solution in Liters
=> moles solute = Molarity x Volume (L)
Apply moles before dilution = moles after dilution ...
=> (Molarity X Volume)before dilution = (Molarity X Volume)after dilution
=> (M)(2.5L)before = (1.2M)(10.0L)after
=> Molarity of 2.5L concentrate = (1.2M)(10.0L)/(2.5L) = 4.8 Molar concentrate
What causes the differences in physical characteristics like hair color among people?
ООО
different versions of genes
O variations in DNA length
different numbers of chromosomes
variations in cell nucleus size
Answers
Answer:
The answer is a
Explanation:
Human population growth in and around cities is called??
Answers
Answer:
Human populations have tended to increase over time. ... The world population has grown significantly, and our economies have become more industrialized over the past few hundred years, and as a result many more people have moved into cities.
Explanation:
This process is known as urbanization.
what is the chemical name for Li2CO2
Answers
Answer:
Lithium Carbonite
Explanation:
Answer:
Lithium
Explanation:
Which two are isotopes of one another?
a. Atoms 1 & 2
b. Atoms 2 & 3
c. Atoms 1 & 3
d. Atoms 1 & 4
Answers
*
Which factor is not involved in the creation of ocean currents?
O The salinity of seawater.
O The unequal heating of the earth
Ships traveling through the ocean
O The rise and fall of ocean tides created by the moon.
Answers
Answer:
Ships traveling through the ocean
Which of the following describes an animal that is contributing to the cycling of water in the hydrologic cycle?
OA. A monkey is cooled as sweat evaporates from its skin.
ОВ. A sea anemone lives in a habitat of seawater.
OC. A fish swims upstream in a flowing river.
OD.
A butterfly hides under tall grass during precipitation.
HELPP!!
Answers
Answer:
OA.
Explanation:
hydrologic cycle invloves evaporation which the wonkey is doing and when t hat condenses it is turned into water which we drink. So if you think very hard about it every time you drink a glass of water, you could be drinking monkey sweat :)
What parts of an atom can change during a nuclear reaction that cannot change during a chemical reaction? The number of neutrons and electrons The number fo protons and neutrons The number of electrons only The number of protons and electrons
Answers
Answer:
The number of protons and neutrons.
Explanation:
Neutrons and Protons can't be removed from nucleus from chemical reactions because they are held together super strong and tight. However, nuclear reactions are strong enough to separate them.
hope this helps :)
Answer:
The number of protons and neutrons
Explanation:
The offsprings' traits depend on which parent the offspring inherited more copies of genes from. agree or disagree
Answers
Answer: disagree
Explanation:
The gene traits of offsprings depends on the inheritance from parent. There will be some dominants traits as well as recessive traits from parents. Hence the statement is incorrect.
What is inheritance?Inheritance is the biological process of transferring genes from parents to offsprings. Identical daughter cells are produced through cell division. Cell division carries through methods such as mitosis, meiosis, binary division etc.
The genetic traits from parents inherited to the offsprings sometimes be equal from both parents and called the homozygous. Whereas the if the traits transferred is unequal it is referred to as heterozygous.
The trends in inheritance is studied well by Griger Mental, who proposed the punnett square to predict the pattern of genetic traits inherited from parents. Hence, the genetic traits both quantitative and qualitative traits are dependant upon both parents and the environmental factors.
To know more on genetic traits, refer here:
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