Answer:
measured
Explanation:
no way can they pin point exactly when something lived when its in the millions
How many atoms are present in 0.035 moles?
Answer:
[tex]2.11x10^{22}atoms[/tex]
Explanation:
Hello!
In this case, considering the Avogadro's number, which relates the number of particles and one mole, we can infer that 1 mole of any element contains 6.022x10²³ atoms as shown below:
[tex]\frac{6.022x10^{23}atoms}{1mol}[/tex]
Thus, we compute the number of atoms in 0.035 moles as shown below:
[tex]atoms=0.035mol*\frac{6.022x10^{23}atoms}{1mol} \\\\atoms=2.11x10^{22}atoms[/tex]
Best regards!
What is 0.000005670 written in proper scientific notation?
A student pours a 10.0mL sample of a solution containing HC2H3O2(pKa=4.8) and NaC2H3O2 into a test tube. The student adds a few drops of bromocresol green to the test tube and observes a yellow color, which indicates that the pH of the solution is less than 3.8 . Based on this result, which of the following is true about the relative concentrations of HC2H3O2 and NaC2H3O2 in the original solution?
Answer:
[HC2H3O2] > NaC2H3O2
Explanation:
The concentration of [tex]\rm HC_2H_3O_2[/tex] has been higher than the concentration of [tex]\rm NaC_2H_3O_2[/tex].
The pKa has been defined as the acid constant that has been used for the determination of the strength of the acid. The higher the pKa value, the weaker the acid has been.
The [tex]\rm HC_2H_3O_2[/tex] has the pka value 4.8 depicting the solution has been a pH 4.8. With the addition of [tex]\rm NaC_2H_3O_2[/tex], the pH has been shifted towards the acidic condition, thus the Hydrogen concentration has been higher.
The change in the pH has been resulted in the reduction in the pH from the basic to acidic condition. Since the concentration of the [tex]\rm HC_2H_3O_2[/tex] has been higher than the [tex]\rm NaC_2H_3O_2[/tex] concentration, the pH has been shifted towards the more acidic condition.
Thus, the concentration of [tex]\rm HC_2H_3O_2[/tex] has been higher than the concentration of [tex]\rm NaC_2H_3O_2[/tex].
For more information about the pH of the solution, refer to the link;
https://brainly.com/question/11936640
What do most mollusks have?
C
Answer:
C- A foot
Particularly a muscular foot.
Answer/Explanation
you"re right they have a foot
Muscular foot for creeping or burrowing. Some also have a head with sense organs.
did u need someone to confirm it or what
Priscilla was building a circuit that used copper wires to connect a battery to a light bulb. As she connected the final wire from the light bulb back to the battery, the light bulb turned on. Priscilla knew that current was now flowing through her closed circuit. What makes the current in the circuit flow? pls help !!!
Answer:
The voltage or potential difference
Explanation:
What makes current flow in a circuit is the voltage or the potential difference.
This force is supplied by the battery or the mains electrical circuit.
Every circuit requires the voltage to drive current through When a circuit is complete, the battery is able to overcome any resistance by the generating enough voltage which is the force to drive the current through.Can some please help me?
1) Balance the equation Fe2O3 + H2SO4 → Fe2(SO4)3 + H2O.
What is the mole ratio of H2SO4 and H2O in the equation?
1:3
3:2
2:1
3:3
2)Balance the equation Mg + Mn2O3 → MgO + Mn.
What is the mole ratio of Mg and Mn in the equation.
1:1
2:1
3:2
4;2
1. The mole ratio of H2SO4 and H2O in the equation = 3:3
2. The mole ratio of Mg and Mn in the equation = 3:2
Further explanationGiven
Reaction
1. Fe2O3 + H2SO4 → Fe2(SO4)3 + H2O
2. Mg + Mn2O3 → MgO + Mn.
Required
Balanced equation
Solution
1. Fe₂O₃ + H₂SO₄ → Fe₂(SO₄)₃ + H₂O
Give a coefficientaFe₂O₃ + bH₂SO₄ → Fe₂(SO₄)₃ + cH₂O
Make an equationFe, left = 2a, right=2⇒2a=2⇒a=1
S, left=b, right=3⇒b=3
H, left = 2b, right = 2c⇒2b=2c⇒2.3=2c⇒c=3
The equation becomes :
Fe₂O₃ + 3H₂SO₄ → Fe₂(SO₄)₃ + 3H₂O
2. Mg + Mn₂O₃ → MgO + Mn.
Give a coefficientaMg + Mn₂O₃ → bMgO + cMn.
Make an equationMn, left=2, right=c⇒c=2
O₂, left=3, right=b⇒b=3
Mg, left = a, right=b⇒a=b⇒a=3
The equation becomes :
3Mg + Mn₂O₃ → 3MgO + 2Mn.
Red blood cells are constantly being produced in your body. Another body system cooperates with the cardiovascular system in the production of these cells. What is this system and how does it cooperate?
What's the purpose of electro cleaning by using electrolysis?
Answer:
Electrolytic cleaning is a method of removing soil, scale or corrosion products from a metal surface by subjecting it as an electrode to an electric current in an electrolytic bath. It is a form of electroplating that can be applied to all electric conductive materials.
when oxygen is available what happens immediately after glycolysis?
NADH IS FORMED
PYRUVATE IS PRODUCED
Oxidative phosphorylation
None of above
Guys pleaaasse i need an answer my final exam will be hours from now
Answer:
NADH is formed
Explanation:
If oxygen exists in the system, pyruvate goes into mitochondrial matrix in order to perform kreb's cycle and forms NADH
Otherwise, pyruvate forms into lactate acid.
Good luck on your final exam
How did the grandmother show her gratitude towards her granddaughter
answer this and in end please tell me how to mark answer as brainliest I will mark your answers as brainliest
Answer:
vgffffgggggvghvxgyfdgubvhumigrrdghg
A student collected a 1.28 g sample of Magnesium. How many atoms of Mg are in his sample?
A student did an experiment that called for 1.24 x 1024 molecules of CaO. What is the mass of her reactant?
A student reacted 0.0405 g of glucose (C6H12O6). How many molecules of glucose did he react?
A digital camera stores images as
A.
digital information.
B.
light.
C.
analog images.
D.
all of these
Answer: A) digital information.
Data is stored in binary fashion as 1s and 0s. If you string enough of them together, you can convey many forms of messages. If you send a message to some kind of storage medium (such as a hard drive or flash drive), then you can retrieve that message at a later date. In effect, you're sending a message to yourself, more or less. By "message", I mean the information about each pixel color that forms the entire image.
In contrast, an analog camera or film camera stores images on film that is to be processed at a later time. Though something like polaroid cameras develop the image fairly quickly without need of a darkroom. Both analog and digital methods involve the use of light to capture the image, and this is true about our eyes needing light as well just to see in general. However, light itself isn't used as a storage method.
Mount Everest is 29,029 feet high. What is
the height of Mount Everest in kilometers?
Answer:
8.849 kilometres
Explanation:
this is the height in kilometers
The metal rhenium becomes superconducting at temperatures below 1.4 K. Calculate the temperature at which rhenium becomes superconducting in degrees Celsius.
Answer:
The temperature at which rhenium becomes superconducting is -271.6 ºC.
Explanation:
We can convert the temperature given in Kelvin, which is an absolute scale, into degrees Celsius. which is a relative scale, by a simple algebraic translation, that is:
[tex]T_{C} = T_{K} - 273[/tex] (1)
Where:
[tex]T_{C}[/tex] - Temperature, measured in degrees Celsius.
[tex]T_{K}[/tex] - Temperature, measured in Kelvins.
If we know that [tex]T_{K} = 1.4\,K[/tex], then the temperature given in degrees Celsius is:
[tex]T_{C} = 1.4\,K-273[/tex]
[tex]T_{C} = -271.6\,^{\circ}C[/tex]
The temperature at which rhenium becomes superconducting is -271.6 ºC.
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Many organisms on Earth exhibit similar ____________.
Question 2 options:
nonliving
characteristics
time
single-celled
Answer:
characteristics i believe
Kp/Kc for reaction for the equilibrium, A(g) ⇌ C(g)+B(g), is _______.
(Kc is the equilibrium constant in terms of concentrations, Kp is the equilibrium constant in terms of pressures, R is the gas constant, T is the temperature)
Select one:
(RT)2
(RT)-1
(RT)-2
(RT)-1.5
RT
Kp/Kc = RT
Further explanationGiven
Reaction
A(g) ⇌ C(g)+B(g)
Required
Kp/Kc
Solution
For reaction :
pA + qB ⇒ mC + nD
[tex]\large {\boxed {\bold {Kc ~ = ~ \frac {[C] ^ m [D] ^ n} {[A] ^ p [B] ^ q}}}}[/tex]
While the equilibrium constant Kp is based on the partial pressure
[tex]\large {\boxed {\bold {Kp ~ = ~ \frac {[pC] ^ m [pD] ^ n} {[pA] ^ p [pB] ^ q}}}}[/tex]
The value of Kp and Kc can be linked to the formula '
[tex]\large {\boxed {\bold {Kp ~ = ~ Kc. (R.T) ^ {\Delta n}}}}[/tex]
R = gas constant = 0.0821 L.atm / mol.K
Δn=moles products - moles reactants or
number of product coefficients-number of reactant coefficients
For reaction :
A(g) ⇌ C(g)+B(g)
number of product coefficients = 1+1=2
number of reactant coefficients = 1
Δn= 2 - 1 =1
So Kp/Kc = RT
What is the IUPAC name of the following compound?
Explanation:
none because they can not be mixed together
How many moles of copper are in 1.51 x 1024 Cu atoms?
2.51 mol Cu
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
1.51 × 10²⁴ atoms Cu
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 1.51 \cdot 10^{24} \ atoms \ Cu(\frac{1 \ mol \ Cu}{6.022 \cdot 10^{23} \ atoms \ Cu})[/tex]Multiply/Divide: [tex]\displaystyle 2.50747 \ mol \ Cu[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
2.50747 mol Cu ≈ 2.51 mol Cu
What kind of intermolecular forces act between a hydrogen cyanide molecule and a potassium cation?
If there is more than one type of intermolecular force that acts, be sure to list them all, with a comma between the name of each force.
(dipole, hydrogen-bonding, dispersion, ion-dipole)
Answer:
ion-dipole
Explanation:
Let us remember that the potassium cation is an ion, a positive ion to be precise.
There is a dipole existing in the hydrogen cyanide molecule. The positive end of the dipole is on hydrogen while the negative end of the dipole is on the cyanide moiety.
The only possible interaction between the potassium cation and the hydrogen cyanide is an ion dipole interaction. The cation interacts with the cyanide moiety having a partial negative charge in the molecule.
Select the correct number of valence electrons, in order, for groups 13-18.
13, 14, 15, 16, 17, 18
5, 6, 4, 3, 8,7
3,4,5,6,7,8
18, 13, 15, 16, 17, 14
Answer:
3,4,5,6,7,8
Explanation:
Groups 13 - 18 are the main group on the periodic table
The group number corresponds the number of valence electrons they contains.
Valence electrons are the number of electrons in the outermost shell of an atom.
So group 13 - 18 corresponds to a valency of 3,4,5,6,7,8.
Groups with a valency of 8 are the noble gases.
How many grams are in 4.58x1023 atoms of oxygen?
In table below, there are descriptions of an experiment on samples of three different chemical compounds. Decide whether the compound is ionic or molecular, if you can. If there is not enough information to decide, choose can't decide in the third column.
compound description lonic or molecular?
1 Compound 1 is a yellow-white solid. When heated to melting, it forms an oily yellow liquid, which is a good electrical insulator.
2 Compound 2 is a hard grayish-white solid. A small 250 mg sample of it is put into a quartz tube and heated strongly. It starts to melt at 1055. °C.
3 Compound 3 is a yellow solid made up of clusters of needle-like crystals. It's a good electrical insulator when solid, but if crushed and dissolved in water, the solution is a good conductor.
Answer:
Compound 1- molecular solid
Compound 2- ionic solid
Compound 3- ionic solid
Explanation:
An ionic solid has a high melting point and does not conduct electricity in solid state. Rather, it's solution or melt is a good electrical conductor.
On the other hand, a molecular solid is a poor conductor of electricity. It has a low melting point and does not easily dissolve in water.
When fat comes in contact with sodium hydroxide, it produces soap and glycerin. Determine whether this is a physical change or a chemical change. Explain your
Answer: Chemical change
Explanation:
Physical change is a change where there is a change in size , shape etc and no new products are formed.
Chemical change is a change where there is a change in chemical composition as new products are formed.
Example: Formation of soap and glycerin from fat and sodium hydroxide is a chemical change as the chemical bonds are getting rearranged to form new products.
How many lead atoms in Pb(OH) 4 ?
4 in hydrogen 4 in oxygen
Explanation:
hope this helps
PLEASE HELP PLEASE LLEASE HELP, WILL MARK BRAINLIEST!!!
Which of the following elements will NOT reach an octet when in a bond?
Answer:
Hydrogen
Explanation:
BRAINLLEST! Boiling water for mac and cheese is a physical change. Give 2 pieces of evidence to support this claim
Answer:
In explanation.
Explanation:
Physical changes are generally changes in states of matter. So, the water going from liquid to gas is a phase change and therefore physical. (It's still water, just in a different form). Im not sure about the second piece of evidence though. Unless you are talking about the Mac and Cheese which in that case is also a physical change as the two ingredients cheese and macaroni stay the same when cooked just become softer and edible.
If you have 2 moles of an element, how many particles do you have?
Answer:
1.204×10^24 particles of element
Explanation:
1mol=6.02×10^23 number of particles (in this case an element)
2mol=(6.02×10^23)×2 particles of the element
=1.204×10^24 particles of element
*be careful aware significant digits
Questlon 23 of 30
What is the term for a large group of people with similar characteristics such
as educational background and income level?
A. An interest group
B. A social class
C. A social culture
O D. A political party
SUBMIT
Many organisms have adaptations which allow them to live in certain environments.
Which structural adaptation would an organism living in a pond most likely develop
if it adapted to a land environment?
A.lungs
B.wings
C.webbed feet
D.sharp eyesight
Answer:
Webbed Feet
Explanation:
Webbed Feet Benefits:
Most animals with webbed feet are aquatic animals who live in, on, or near the water. Webbed feet help them move quickly through the water when they're chasing food or trying to escape from predators.
Kp/Kc for reaction for the equilibrium, A(g) ⇌ C(g)+B(g), is _______.
(Kc is the equilibrium constant in terms of concentrations, Kp is the equilibrium constant in terms of pressures, R is the gas constant, T is the temperature)
Select one:
(RT)2
(RT)-1
(RT)-2
(RT)-1.5
RT
RT
by using relation between Kp and Kc we get the above answer