Answer:kj
Explanation:nnn
different type of flatbread
3. How many moles are in 1.49 x 1023 molecules of iodine?
Answer:
The answer is 0.25 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{1.49 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{1.49}{6.02} \\ = 0.247508305...[/tex]
We have the final answer as
0.25 molesHope this helps you
6. There are three isotopes of silicon. They have mass numbers of 28, 29 and 30. The average atomic mass of silicon is 28.086amu. What does this say about the relative abundances of the three isotopes?
Answer:
That means that the isotope that has a mass number of 28 is probably the most abundant. This is because your average atomic mass is 28.086 amu, which is closest to 28.
Formula used to calculate average atomic mass follows:
average atomic mass=(atomic mass of an isotope)*(fractional abundance)
we are given=
Three isotopes of Silicon, which are Si-28, Si-29 and Si-30.
Average atomic mass of silicon = 28.086 amu
As, the average atomic mass of silicon is closer to the mass of Si-28 isotope. This means that the relative abundance of this isotope is the highest as compared to the other two isotopes.
Percentage abundance of Si-28 isotope = 92.2%
Percentage abundance of Si-29 isotope = 4.7 %
Percentage abundance of Si-30 isotope = 3.1%
Hence, the abundance of Si-28 isotope is the highest as compared to the other isotopes.
:answer question number 10
Answer:
the last one
Explanation:
I'm pretty sure
Answer:
Particles on each are constantly moving (the last one)
Mention any three ways of making salt. (please help me Asap)
How do you calculate wavelength and frequency?
Answer:
Wavelength can be calculated using the following formula: wavelength = wave velocity/frequency. Wavelength usually is expressed in units of meters. The symbol for wavelength is the Greek lambda λ, so λ = v/f.
Explanation:
Just a formula that's commonly used in biology.
WILL GIVE BRANLIEST!!
Carbon tetrachloride (CCl4) is
ionic
covalent
Answer:
Covalent
Explanation:
In the carbon tetrachloride molecule, four chlorine atoms are positioned symmetrically as corners in a tetrahedral configuration joined to a central carbon atom by single covalent bonds
Answer:
Carbon tetrachloride (CCl4) is ✔ covalent.
Answers to assignment question:
What properties would you expect for CCl4? Select all that apply.
It is likely a gas or liquid at room temperature.
It is likely soluble in water.
It will likely light up a bulb in a conductivity apparatus.
It will likely have a high melting point.
Calcium oxide (CaO) is ✔ ionic.
What properties would you expect for CaO? Select all that apply.
It is likely a gas or liquid at room temperature.
It is likely soluble in water.
It will likely light up a bulb in a conductivity apparatus.
It will likely have a high melting point.
Explanation:
all correct on edge! :D
What is the molar mass of H2SO4?
Answer:
98.08g/mol is your answer
Explanation:
hope this helps
Which of the following is an example of Newton’s 2nd Law? A. A bowling ball requires more force to roll than a tennis ball B. Sitting in a chair C. A rocket blasting off D. All of the above
Answer:
The answer is A.
Explanation:
A chemist titrates 100.0 mL of a 0.3065 M aniline (C6H5NH2) solution with 0.5774 solution at 25 . Calculate the pH at equivalence. The of aniline is .
Answer:
4.91
Explanation:
From the given information:
The millimoles of aniline = 100* 0.3065 = 30.65
30.65 millimoles HNO3 must be added to reach the equivalence point.
30.65 = V x 0.5774
V = 30.65/0.5774
V = 53.08 mL HNO3 must be added
Thus, total volume = 53.08 + 100 = 153.08 mL
[salt] = 30.65 / 153.08 = 0.20022 M
At equivalence point :
pOH = 1/2 [pKw + pKb + logC]
pOH = 1/2 [14 + 4.87 + log 0.20022 ]
pOH =9.086
pH = 14 - 9.086
pH = 4.914
pH ≅ 4.91 to 2 decimal places.
BRAINLIEST! Please help me answer the following questions:
1) How do you find the valency of an element?
2) How do you determine if an element is nuetral/an isotope/ or an ion?
If you could help with 1 or both questions I would really appreciate it :)
Explanation:
1) from the periodic table for example if u looking for K it is from the group 1A so the valancey = +1 that is mean it loses one electron to reach a stable state. and this applied for the 1A , 2A, 3A groups.
if u looking for N it is from group 5A so its valency is -3
so it gain 3 electrons to reach a stable state to complete its orbital to 8 electrons. this applied to 5A, 6A,7A
for the transition metals and simimetals other rules.
2) neutral if the element does not hold any charge like
H2, O2, N2, Fe, Au, Cu ...
isotope : if the 2 elements have same symbol and atomic number but they differ in the mass number because the have different numbers of neutrons.
if the element is charged then it is considered as an ion ex: Fe2+ then it is iron cation ( +ion)
F- then it is fluoride anion (-ion)
if u have any doubt just writ a comment ( ;
A copper rod takes up 75 mL of space. With a density of 8.96 g/mL, what is the mass of the rod
Which statement describes how chemical formulas, such as H2O, represent compounds?
They show the types of molecules that make up an atom.
They show the elements that make up a compound.
They show the three-dimensional shape of a molecule.
They show the types of bonds that exist between elements.
Answer: B. They show the elements that make up a compound
Explanation:
Answer:
B
Explanation:
How would you ask a girl out. I know that I can use my voice, but I don’t know what to say.
Answer:
Just go out there and be yourself brother!
Explanation:
If she doesn't like you, she doesn't like the real you, therefore you don't deserve her! lol
Which of the choices is an example of an element?
O CO
O Co
O C2H2O2
O CO2
Answer:
Co(cobalt) is the answer
Explanation:
Cobalt is a chemical element with the symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.
Continental waters are classified into two categories Lentic and Lotic. Ecosystem has flowing waters; such as creeks, streams, rivers, springs, brooks and channels. A lentic Ecosystem has still waters such as ponds, marshes,ditches, reservoirs, and lakes. The ecosystem of Lentic and Lotic waters includes biotic (Living) interactions between plants, animals and micro- organisms, and abiotic (non living) physical and chemical interactions.
A) Fish
B) algae
C) Bacteria
D) water flow
Answer:
it is D
Explanation:
write this number in scientific notation 41, 820, 000
Answer:
4·1×10∧-7Explanation:
[tex]\mathrm {Hey, there!}[/tex]
Let's solve your problem -
The answer to the question is 4.18 10^7.
Here is my clarification/explanation to support:
To convert a standard number to scientific notation, we have to move the decimal point up until we have a 1 digit number.
When we keep moving the decimal point, we get 4.18
Now, we will count the numbers after the 8 to get the 10 area.
There are five numbers after the 8, so we get 10^5.
Now, we will add 2 more to the 5, we get 10^7
Our answer will be: 4.18 10^7
[tex]\mathrm {Best, of, Luck!}[/tex]
The question asks me to classify the reaction
CO2 (g)+H20(1) H2CO3 (aq)
Which option is an Ionic Compound
A.LiCl
B.CO
C.No2
D.So3
Answer:
LiCI
Explanation:
CO and No2 are both covalent compounds and it was a 50 50 and I guessed the right answer.
The one that is an ionic compound is LiCl. The correct option is A.
What are ionic compounds?
Ionic compounds are those compounds that have one negative and one positive charge molecule. When this negative and positive charge joins together, the compound becomes neutral. Electrostatic force joins these elements.
LiCl is a salt that is formed by the joining of lithium with chloride. Lithium is positively charged and chlorine is negatively charged. One identity of this compound is that it is a neutral salt, so it can be identified as an ionic compound. When they disjoint, they form a crystal-like structure.
An example of an ionic compound is sodium chloride, in which sodium is positive and chloride is negative.
Therefore, the correct option is A. LiCl.
To learn more about ionic compounds, refer to the link:
https://brainly.com/question/9167977
#SPJ2
Please answer it!! Would appreciate it!
[tex] \sf \: Answer \: 8 \: :[/tex]
→ During the formation of a chemical bond, heat is released.
[tex] \sf \: Answer \: 9 \: :[/tex]
→ Solution that contains all the solute it can hold at a given temperature is saturated.
[tex] \sf \: Answer \: 10\: :[/tex]
→ No. of neutrons present in Bromine are 44
Chemical bonding is the combining of elementa to form
-energy levels
-atoms
-electrons
-compounds
which best explains why a scientist would share these details in a conference?
a it tells the audience if the results support or contradict the hypothesis
b it tells the peers if the study is supported by mathematical models
c it informs the peers of the results are supported by other scientists
d it informs the audience if the study included controlled tests
The question is incomplete, the complete question is; During a conference presentation, a scientist described the materials that she used and how she performed her experiments.
Which best explains why a scientist would share these details in a conference?
It tells the audience if the results support or contradict the hypothesis.
It tells the peers if the study is supported by mathematical models.
It informs the peers if the results are supported by other scientists.
It informs the audience if the study included controlled tests.
Answer:
It informs the audience if the study included controlled tests.
Explanation:
Usually, scientific conferences involve presentation of papers by scientists. These paper presentations are actually the sharing of details of the scientific research carried out by other scientists.
Presenting the materials and methods section of the a research project to a scientific conference informs the audience if the study included controlled tests.
The inclusion of controlled tests in a scientific study enhances the validity of the results obtained in the study.
Each atom of an element has the following electron configuration.
1s22s22p63s23p64s23d104p65s24d105p5
What is the name of the element?
what is the ionic compound formula sodium nitride?
Answer:
In ionic compounds, the charges of constituent ions must balance. This can be achieved by having three sodium ions per nitride ion. Therefore, the formula of sodium nitride is Na3N
Explanation:
Answer:
the charges of constituent ions must balance. This can be achieved by having three sodium ions per nitride ion. Therefore, the formula of sodium nitride is Na3N
Explanation:
Which option will increase the rate of reaction?
Answer:
Explanation:
there's no options that you put but usually if you add more of the reactant the rate will increase, adding a catalyst will increase the rate, and increasing the temperature if it's endothermic
A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at
37°C. The student repeated the investigation five times
Figure 11 shows the results
time taken for amylase to produce glucose (s)
Test 4
120
125
110
115
Figure 11
() Calculate the rate of amylase enzyme activity for the 10% starch solution.
Answer:
Phenolphthalein is an indicator. It is pink in alkaline solutions and turns colourless as the pH decreases.
It can be used to measure the activity of the enzyme lipase on the breakdown of lipids.
Samples of milk containing phenolphthalein were incubated with lipase at different temperatures.
The time taken for the phenolphthalein to turn colourless was recorded and used to calculate the rate of enzyme activity.
Figure 10 shows these results.
Picture
(a) (i) Explain why phenolphthalein turns colourless when lipase breaks down the lipids in milk. (2)
(ii) Describe the effect of temperature on the activity of lipase, as shown in Figure 10. (2)
(iii) Explain why the activity of lipase changes above a temperature of 40°C. (2)
(b) A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at 37°C. The student repeated the investigation five times.
NEED HELP ASAP!!!!! PLEASE HELP!!!!! NEED HELP ASAP!!!!!
Directions: Name the covalent compound created.
EXAMPLE- Sr3P2= Tristrontium diphosphide
CH4 =
B2Si =
N2O5 =
CO2 =
Answer:
CH4 - Methane
B2Si - Diboron monosilicide
N2O5 - Dinitrogen pentoxide
CO2 - Carbon dioxide
Explanation:
When it comes to naming covalent compounds, there are several rules.
The name is derived based on the formula. For example, N2O5. The first element is nitrogen. To the name of the element, you add the prefix that tells us how many of its atoms are in the compound. In this case, there are two atoms, which means that the prefix will be di- (dinitrogen). The second element is oxygen. You are supposed to take only the root of the second element's name and then add the prefix denoting the number of its atoms and the suffix -ide (pentoxide). This is how we'll get dinitrogen pentoxide.
The only exception is methane (CH4), which is an organic compound. Organic compounds are named using the IUPAC nomenclature.
Pleaseeesseeeeesssseredseeeesss
Answer:
B. Electrons travel through the sol
Explanation:
thats your answer :)
What are the parts of an electron configuration?
Answer:
Explanation:
electronic confirmation=1s^2,2S^2,2P^6,3S^2
atomic no.is 12 therefore :- this is magnesium
Period=3
Block=s-block
Group=II A
Tubbo or TommyInnit? Choose wisely.
Answer:
Tubbo
Explanation:
more informational