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4.250 x 10-6 nm in standard form , please help!!
Answer: 4,250 x 10 - 6
Explanation: ok so we have a decimal number, what you do with that is
[tex]4.250 x 10^{3}[/tex] = 4.250 x 1,000 = 4,250 now you can just move the decimal every time without that equation but its better safe. I'm pretty sure that's how they want it, because its not expanded or word.
gots another for you guys thanks inn advance
Answer:
c. the center of curvature of the two sides of the lens
If an object has a mass of 43.23 g and a volume of 32.1 mL, what is its density? Show your work!
Answer: 1.34 g/ml
Explanation: Density is an objectives mass divided by it's volume:
(43.23 g)/(32.1 ml) =1.34 g/ml
A compound contains only carbon, hydrogen, and oxygen. Combustion of 8.544 mg of the compound yields 12.81 mg CO2 and 3.50 mg H2O. The molar mass of the compound is 176.1 g/mol. What are the empirical and molecular formulas of the compound
Answer:
The empirical formula is the formula with a minimum whole number ratio of the constituent atoms present in a molecule. While the molecular formula has the actual number of atoms of various elements present in the molecule of the substance.
Empirical formula is C₃H₄O₃
Molecular formula is C₆H₈O₆
This question involves finding the empirical and molecular formulas. Empirical formula is the one where minimum whole number ratio of the constituent atoms present in a molecule is shown whereas molecular formula is the one that shows the number of each type of atom that are present in a molecule.The compound contains only carbon, oxygen and hydrogen and undergoes combustion. Thus;[tex]C_{x}[/tex][tex]H_{y} O_{z}[/tex] + O₂ ⟶ xCO₂ + [tex]\frac{y}{z} H_{2} O[/tex]
The combustion yields 12.81 mg of CO₂.From online sources, molar mass of CO₂ = 44 g/mol
number of moles of CO₂ = 12.81/44 = 0.291m mol
Mass of carbon in it is; C = 12 × 0.291 = 3.492 mg
Similarly the combustion yields 3.50 mg H2O.molar mass of water = 18 g/mol
number of moles of water in it = 3.5/18 = 0.194m mol
Hydrogen has 2 nos in water and so;
number of moles of hydrogen = 2 × 0.194 = 0.388m mol
Mass of hydrogen = 1 × 0.388 = 0.388 mg
Compound is 8.544 mg and so;Oxygen mass = 8.544 - (3.492 + 0.388) = 4.664 mg
Similarly, moles of oxygen that has molar mass of 16 is;
no of moles of oxygen = 4.664/16 = 0.2915m mol
Thus;Ratio of C:H:O is; 0.291:0.388;0.2915
Simplifying this gives us the empirical formula ratio as;
3:4:3
Thus;
Empirical formula is C₃H₄O₃
Molar mass of C₃H₄O₃ = (12 × 3) + (1 × 4) + (16 × 3) = 88 g/molWe are told that the molar mass of the compound is 176.1 g/mol.
Thus;
Molecular formula is; (176.1/88)C₃H₄O₃ = C₆H₈O₆
Read more at; brainly.com/question/14853529
If zinc has an atomic number of 30 and a mass number of 65 what is the correct number of protons neutrons and electrons ?
Answer:
protons 30
neutrons 35
electrons 30
Element Z has 2 natural isotopes. One isotope has a mass of 15.0 amu and a relative abundance of 30%. The other isotope has a mass of 16.0 amu. What is the second isotope's relative abundance?
Answer:
70%
Explanation:
Just substract 100 % - 30%
Which of the following statements about alcohols is false?
A. Ethanol is soluble in water.
B. Ethanol has a higher boiling point than ethane.
C. Ethanol produces hydrogen when it burns.
D. None of these
Answer:
It's C. Ethanol produces hydrogen when it burns
When burned, ethanol produces water and CO2.
Please help me with this chemistry
Answer:
D=1.56g/mL
Explanation:
Density=m/v
D=14.06g/(24mL-15mL)
D=14.06g/9mL
D=1.56g/mL
white vitriol molecular formula
and green vitriol molecular formula??
Answer:
Green vitriol- FeSO4·7H2O
white vitriol- ZnSO₄
English
M.
3.x - 9
2r-7
.X + 2
18
Answer:
it will come answer 21 write
there are 3 isotopes of the element Gz: Gz-80,Gz-81,Gz-83. the average atomic mass of Gz is 82.74. what is the most abundant isotope of Gz? (please type the mass number only )
The most abundant isotope is Gz-83 because the average atomic mass of Gz is closer to 83.
The average atomic mass is defined as the weigthed mean of the isotopes.
The mass of the isotopes is 80, 81 and 83 uma, respectively.
As the average atomic mass (82.74uma) is closer to the atomic mass of Gz-83 than the mass of the other isotopes, you can interpretate that the most abundant isotope is Gz-83.
Learn more about average atomic mass in:
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Which of the following statements is not true about ecosystems?
a. A healthy ecosystem can support an unlimited number of life forms.
b. Predators play a role in balancing the earth's ecosystems.
c. People's activities can improve the health of an ecosystem.
d. The parts of an ecosystem depend on each other.
Answer:
A
Explanation:
though an ecosystem can support life forms,when they become over populated or unlimited there will be competition for food,Shelta and other basic necessities which will lead to many of these life forms dying
will mark brainliest if correct
Which methods separate a mixture according to the size of the particles?
a
filtration and chromatography
b
distillation and chromatography
c
filtration and evaporation
d
distillation and evaporation
Answer:
filtration and chromatography
Explanation:
I hope this will help you :-)
In your conversion from Milli- to Centi- units, would you move the decimal point to the left or the right?
Answer:
one unit to the left
Explanation:
cm are 10 times mm, so to convert you have to divide by ten
Examples
100 mm = 10,0 cm
0.50 mm = 0.05 cm
Vapor pressure of any liquid _______. A. increases with increases in temperature B. increases with decreases in temperature C. is not affected by changes in temperature D. increases with increases in volume of the liquid E. None of the Above
Answer:
increase with increases in temperature
Explanation:
please mark me brainleast
briefly explain how to separate a mixture of water, kerosene, sawdust and nahso4?
Answer:
Use filtration method lol.
cuantos gramos de soluto y solvente tendra 127 gramos de solición cuya concentración es 14% m/m ayuda para resolverlo
banetshegtsjegsgeheb
What is the change of state in which a gas becomes a liquid?
Answer:
Condensation
Explanation:
Answer:
Condensation
Explanation:
When a gas changes to a liquid it is known as condensation. It happens when molecules in a gas slowly reduce their movement speed.
HOPE THIS HELPED
Help!! due tomorrow
.
Answer:
It's B. The molecules in the system have more kinetic energy than a solid.
!!DUE TODAY, NEED HELP ASAP!!
A student measured the masses of some aluminum and copper cylinders of different volumes. The data is displayed below:
Aluminum: Copper:
Volume (mL)
Mass (g)
Volume (mL)
Mass (g)
3.7
9.99
1.8
16.02
6
16.2
2.3
20.47
8.5
22.99
3.5
31.15
10.74
29
4.2
37.38
15
40.5
5.8
51.62
On graph paper graph the data above on ONE graph. Use the graph paper so the longer side is your y-axis.
Use up the majority of the graph paper. Do not make a small graph!
Use a ruler/straight edge so you graph is neat.
You will need to plot the points for each substance and create a double line graph. When connecting your points for each substance, continue the lines past the plotted points.
Be sure to include a key to identify the substances.
Make your X-axis volume(mL) and your Y-axis mass(g)
Look at the numbers for both substances when creating your scales. You will most likely have a different scale for mass and volume. What is the lowest number? What is the highest number? What does it make sense to go by?
Calculate the density of each metal.
Aluminum:_________________________ Copper:________________________
What happens to the mass of the copper at the volume increases from 6 to 8mL?
Which sample is more dense? How does the graph show you this?
Answer: The data are not arranged in a useful pattern. I arranged them as best I could and made a graph in Excel for demonstration.
Explanation: The data are plotted with mass on the x axis and volume on the y. Add a key to identify the top line as CU and the bottom as Al.
The density of Cu is 8.9 g/ml and 2.70 for Al.
The mass of copper increases by 17.8 grams going from 6 to 8 ml. (8.9 g/ml)*(2 ml) = 17.8 grams.
Copper is more dense. c The graph shows that for the same volumes, copper has the higher mass.
Density and Years: What do you know?Objectives: determine and compare density of pennies to assess composition. Procedure:1. Read the directions and create a data table accordingly.2. Place 15-20 pennies in order of consecutive dates. Find the mass of each penny and record.3. Find the volume of all 5 pennies by water displacement and record in your data table. Record the volume adding 5 more pennies at a time until you have measured them all (15-20).a. Find the average volume of 1 penny.4. Calculate the density of each penny and graph according to the year.5. If the density of copper is 8.96 g/cm3 what would the mass of a pure copper penny be?6. Draw a conclusion.7. How might this relate to a real world example?
Answer:I dunno
Explanation:it is the best thing I ever said in this app
What makes an atom radioactive?
Answer:
The unstable nucleus of radioactive atoms emit radiation.
Explanation:
When the atoms of an element have extra neutrons or protons it creates extra energy in the nucleus and causes the atom to become unbalanced and unstable, or radioactive.
(https://www.epa.gov/radtown/radtown-radioactive-atom-activity-4-atomic-stability)
Answer:
When the atoms of an element have extra neutrons or protons it creates extra energy in the nucleus and causes the atom to become unbalanced or unstable. Whether radioactive elements can become stable and if so, how. The unstable nucleus of radioactive atoms emit radiation. ... This process is called radioactive decay.
Explanation:
A sample of brass weighing 1.203g was analyzed. The zinc in the alloy was reacted with 35.123g of HCl in excess, according to the balanced equation:
Zn (s) + 2HCl(aq) - > H2(g) + ZnCl2 (aq)
After all the zinc reacted, the mass of the remaining solution weighed 36.309g
What was the mass of H2 produced?
What mass of Zn reacted?
What was the percentage of Zn (by mass) in the alloy?
The number of moles of reactants and products can be used to obtain the mass of products formed. The results obtained are as follows;
The mass of hydrogen produced is 0.0174 gramsThe mass of zinc produced is 0.5688 gramsThe percentage by mass of zinc in the brass alloy is 47.3 %The question says that HCl was in excess. It means that after the reaction, we will have unreacted HCl(aq) and ZnCl2(aq) in the remaining solution.
Hence;
Mass of ZnCl2(aq) formed = 36.309g - 35.123g = 1.186g
Number of moles ZnCl2(aq) formed = [tex]\frac{mass of ZnCl2(aq) formed}{molar mass of ZnCl2}[/tex]
[tex]\frac{1.186g}{136.286 g/mol}[/tex] = 0.0087 moles
From the reaction equation;
[tex]Zn (s) + 2HCl(aq) - > H2(g) + ZnCl2 (aq)[/tex]
To obtain the amount of Zn reacted
1 mole of Zn yields 1 mole of ZnCl2
x moles of Zn yields 0.0087 moles of ZnCl2
x = 0.0087 moles of Zn
a) 1 mole of Zn yields 1 mole of H2
0.0087 moles of Zn yields 0.0087 moles of H2
Mass of H2 = 0.0087 moles of H2 * 2 g/mol = 0.0174 grams
b)
Mass of Zn reacted = 0.0087 moles of Zn * 65.38 grams/mole = 0.5688 grams
c)
Percentage of Zn in the alloy = 0.5688 grams/1.203g * 100 = 47.3 %
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Help Please I need to finish TODAY
Answer:
A. > digestive and circulation
B. > digestive and excertory
C. > nervous and muscluar
D.> digestive and circulation
hope this helps !! please make brainlest!
what is sublimation
Explanation:
Sublimation is the conversion of a substance from the solid to the gaseous state without its becoming liquid. ... Freeze-drying of food to preserve it involves sublimation of water from the food in a frozen state under high vacuum. See also vaporization; phase diagram.
Chewing food to break it down into smaller particles represents a physical change, but the charging of starch into sugars by enzymes in the digestive system represents a chemical change.Chemical or physical change?
Answer:
Chemical changeExplanation:
The charging of starch into sugars by enzymes in the digestive system shows a chemical change.[tex]\tt{ \green{P} \orange{s} \red{y} \blue{x} \pink{c} \purple{h} \green{i} e}[/tex]
which elements are liquid in the periodic table?
can any one tell me same for ALCL3 I need it urgently plzzz
Lets Form bonds
Al=2,8,3
Lets Write actual configuration or modern
[tex]\\ \sf\longmapsto 1s^22s^22p^63s^3[/tex]
It has valency +3Cl:-2,8,7Let's write configuration
[tex]\\ \sf\longmapsto 1s^22s^22p^63s^23p^5[/tex]
It has valency -1Now Criss cross valency (Refer to attachment)
We get
[tex]\\ \sf\longmapsto AlCl_3[/tex]
ANSWER QUICK PLEASE!!!! 25 POINTS
Acrylonitrile and ethyl acetate have the same boiling point: 77.2ºC. In one to two sentences, explain what outcome you would expect if a mixture of these two substances were distilled.
The two substances can never be separated by distillation because distillation depends on difference in boiling point.
Distillation is a separation method that depends on difference in boiling point between two substances.
Usually, the substance having a lower boiling point is collected first as the temperature is gradually raised. The substance having a higher boiling point then follows.
However, since the two substances have the same boiling point, they can not be separated by distillation because they will be converted to vapor simultaneously thereby making separation impossible.
Learn more: https://brainly.com/question/15946045
Describe the color change that would be observed in water in left hand beaker
Answer:
is there supposed to be a photo with this?
Explanation:
