Physical or Chemical change?
Answer: Chemical Change
Explanation:
because it probably doesnt change the physical anatomy of the object only the atoms/ molecule relations
How many elements are present in the compound RbMnO4?
how many moles are in a 25.0 grams of carbon dioxide
answer:44.0095
Explanation:
sana makatulong
Answer:
44.0095
Explanation:
We assume you are converting between grams CO2 and mole. You can view more details on each measurement unit: molecular weight of CO2 or mol This compound is also known as Carbon Dioxide. The SI base unit for amount of substance is the mole.
Accreditation of laboratories that do forensic investigations is:_________
a. always required
b. done voluntarily
c. done using independent nongovernmental agencies such as ASTM and ISO
d. done by a special government agency to insure uniformity of testing and results across all laboratories is never done since this
e. is expensive and does not improve the results obtained by the laboratory
Answer:
a. always required
Explanation:
Accreditation of laboratories is a mandatory requirement for forensic science providers. To manage the quality of services provided by the forensic laboratories, Accreditation, Certification, and Interagency Working Group have found it necessary to make the accreditation of forensic laboratories mandatory.
This will instill confidence in the public and ensure that the services rendered by them are always accurate and up to standard.
The reaction A→B is to be carried out isothermally in a continuous-flow reactor. Calculate the PFR volume to consume 99% of A (CA = 0.01CA0) when the entering molar flow rate is 5 mol/h (assume pure A), the volumetric flow rate is constant at 10 dm3 /h and the rate is: -rA=3CA 2 [ dm3 /mol•h]
Answer:
Explanation:
From the information above:
The equation for the reactor volume of CSTR is given by the formula:
[tex]V = \dfrac{C_{Ao}V_o - C_A V_o }{-rA}[/tex]
[tex]V = \dfrac{C_{Ao}V_o (1 - 0.01)}{KC_A^2}[/tex]
The reaction rate of A is:
[tex]-r_A = kC_A^2[/tex] and k = 3 dm³/mol.h
replacing the values in the above equation to solve for v;
∴
[tex]V = \dfrac{(0.5 \ mol/dm^3) (10 \ dm^3/h) (1 - 0.01)}{ ( 3 \ dm^3/mol.h) (0.01 \times 0.5 \ mol/dm^3)^2}[/tex]
V = 66,000 dm³
Thus, the reactor volume of CSTR is 66000 dm³
Taking the differential mole balance equation for PFR is as follows:
[tex]\dfrac{d(C_AV_o)}{dV} = -r_A[/tex]
[tex]\dfrac{d(C_AV_o)}{dV} = Kc^2A[/tex]
Taking the integral between initial and final concentrations;
[tex]\dfrac{v_o}{k} \int ^{C_A}_{C_{Ao}} \dfrac{dC_A}{C^2A}= - \int ^V_o \ dV[/tex]
[tex]V = \dfrac{V_o}{K} \Big [\dfrac{1}{C_A}- \dfrac{1}{C_{Ao}} \Big ][/tex]
replace the values in the above equation;
[tex]V= \dfrac{(10 \ dm^3/h) }{(3 \ dm^3/mol.h)}\Big [ \dfrac{1}{0.01(0.5 \ mol/dm^3)} - \dfrac{1}{0.5 \ mol/dm^3} \Big ][/tex]
[tex]\mathbf{V = 66 0 \ dm^3}[/tex]
Thus, the reactor volume of PFR is 660 dm³
Predict the chemical formula of the compound that will form when Li and o interact.
Answer:
[tex]Li_2O[/tex]
Explanation:
Hello!
In this case, when looking over the chemical formula of a compound formed when two elements interact, we need to realize about their location in the periodic table; thus, since lithium is a metal and oxygen a nonmetal, we infer lithium turns out the cation and oxygen the anion. Moreover, as the oxidation state of lithium is 1+ and that of oxygen is 2-, we can set up the chemical formula as follows:
[tex]Li^+O^{2-}\\\\Li_2O[/tex]
Best regards!
a rock that is pushed down a hill represents both potential and kinetic energy. which statement best represents the energy transformation involved in this scenario
Explanation:
kinetic energy Increases due to gravity. A rock being pushed down a hill increases in speed, due to gravity, what goes up must come down....
How does latitude affect water temperature? Choose ALL that apply Lesson 2.05 none of the choices Temperatures are greatest at low altitudes because of the proximity to the equator As you move to higher latitudes approaching the poles, the temperature decreases. Temperatures are lowest at low altitudes because of the proximity to the equator
Answer:
I think it's option 3 (From top to bottom)
Explanation:
When the water is at a higher altitude there's only about 40 percent heat that the equator does.
Explain how the processes of photosynthesis and respiration are related to each other
Answer:
Explanation:
The end product of Photosynthesis is glucose that is used in cellular respiration to make ATP. The glucose is then turned back into carbon dioxide, which is used in photosynthesis. While water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.
ou are a work study for the chemistry department. Your supervisor has just asked you to prepare 500 mL of 3 M HCl for tomorrow’s undergraduate experiment. In the stockroom explorer, you will find a cabinet called "stock solutions". Open this cabinet to find a 2.5 L bottled labeled "11.6 M HCl". The concentration of the HCl is 11.6 M. Please prepare a flask
Answer:
Add to a 500mL volumetric flask 300mL of water, the 129mL of the 11.6M HCl solution and then complete to volume with water
Explanation:
To make 500mL = 0.500L of a 3M HCl from the 11.6M HCl stock we need first to find the moles of HCl we need:
Moles HCl:
0.500L * (3mol / L) = 1.5 moles of HCl are needed
These moles are obtained from the 11.6M HCl solution. The volume required is:
1.5mol * (1L / 11.6moles HCl) = 0.129L = 129mL must be added to the solution.
That means to prepare the 500mL of the 3M HCl you need to:
Add to a 500mL volumetric flask 300mL of water, the 129mL of the 11.6M HCl solution and then complete to volume with water
Answer:
Calculation: 11.6 M × V = 3.0 M × 0.500 liters
V = 0.13 liters
Steps for dilution:
Measure out 0.13 liters of the concentrated solution of 11.6 M HCl using a volumetric pipet.
Transfer this into solution into a 500 milliliter volumetric flask.
Add water to the flask until it reaches a total volume of 500 milliliters.
Solution: V = 0.13 liters
Explanation:
(ILL GIVE 100 POINTS AND EDIT IT AND MARK BRAINLIEST) Examine the diagram of the cell cycle. Which label identifies the stage in which the DNA is copied and the cell grows? W X Y Z
Answer:
where is diagram. sorry.
One way to represent this equilibrium is: 2 Al(s) 3 Br2(l)2 AlBr3(s) We could also write this reaction three other ways, listed below. The equilibrium constants for all of the reactions are related. Write the equilibrium constant for each new reaction in terms of K, the equilibrium constant for the reaction above.
The question is incomplete, the complete question is;
Aluminum metal and bromine liquid (red) react violently to make aluminum bromide (white powder). One way to represent this equilibrium is:
Al(s) + 3/2 Br2(l)AlBr3(s)
We could also write this reaction three other ways, listed below. The equilibrium constants for all of the reactions are related. Write the equilibrium constant for each new reaction in terms of K, the equilibrium constant for the reaction above.
1) 2 AlBr3(s) 2 Al(s) + 3 Br2(l)
2) 2 Al(s) + 3 Br2(l) 2 AlBr3(s)
3) AlBr3(s) Al(s) + 3/2 Br2(l)
Answer:
See explanation
Explanation:
We have that; Al(s) + 3/2 Br2(l)AlBr3(s)
So;
Al(s) + 3/2 Br₂(l) = AlBr₃(s)
K = [ AlBr₃] / [ Al] [ Br₂]³/²
K² = [ AlBr₃]² / [ Al ] ² [ Br₂]³
Now;
1) 2 AlBr₃ = 2 Al(s) + 3 Br₂(l) =
K₁ = [ Al ] ² [ Br₂]³ / [ AlBr₃]²
K₁ = ( 1 / K² ) = K⁻²
For the second reaction;
2 ) 2 Al(s) + 3 Br₂(l) = 2 AlBr₃(s)
K₂ = [ AlBr₃ ]² / [ Al ]² [ Br₂ ]³
K₂ = K²
For the third reaction;
3 )
AlBr₃(s) = Al(s) + 3/2 Br₂(l)
K₃ = [ Al ] [ Br₂ ] ³/² / [ AlBr₃ ]
= ( 1 / K ) = K⁻¹
Based on the type or types of intermolecular forces, predict the substance in each pair that has the higher boiling point Match the words in the left column to the appropriate blanks in the sentences on the right. Make certain each sentence is complete before submitting your answer Reset Help stronger dispersion forcesG Given the molecules propane (C3Hs) and n-butane (C4H10), Г- has the higher boiling point mainly due to n-butane (C,H Given the molecules diethyl ether (CH3 CH2OCH2 CHs) and 1-butanol (CH3 CH2CH2 CH2OH) higher boiling point mainly due to 1-butanel CH,CH, CH,CH,OH) diethyl ether (CH CH,OCH CH, has the propane (C, H ts greater melar mass
Answer:
C4H10 has a higher boiling point due to stronger dispersion forces
1-butanol has the greater boiling point mainly due to hydrogen bonding influences
Explanation:
If we consider propane and n-butane, we discover that they are both alkanes. However, the magnitude of dispersion forces in alkanes depends on the length of the carbon chain. The greater the length of the carbon chain is greater in n-butane than in propane. The greater the chain length, the greater the magnitude of dispersion forces and the greater the boiling point. Hence, n-butane has a higher boiling point than than propane.
Also, if we compare the boiling points of 1-butanol to that of diethyl ether, we will discover that 1-butanol has a higher boiling point mainly due to intermolecular hydrogen bonding influences.
Which bond would require more energy to break apart? (Short bond or Long bond). Explain
a) longer bond. because the charges are further apart
b) shorter bond. because the charges are closer together
c) shorter bond. because the charges are both positive
d) longer bond. because the charges are closer together
Answer:
shorter bond, because charges are close apart
Explanation:
shorter the bond length more is the energy required to break the bond for example if you take three pencils of different sizes one longer One medium sized One Shot sized if you try to break them the longer pencil will break much faster than the other two because the greater the length the lesser the strength the lesser energy you need to apply to break them apart ...
hope you understand
What are the different elements that make up a molecule of glucose?
Answer:
Glucose has a chemical formula of: C6H12O6 That means glucose is made of 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms. You will be building one type of sugar called glucose.
Explanation:
To determine the freezing point depression of a LiCl solution, Toni adds 0.317 g of LiCl to the sample test tube along with 20.5 mL of distilled water. Determine the concentration, in molality, of the resulting solution. MW of LiCl is 42.394 g/mol Density of H2O is 0.9982 g/mL
Answer:
0.365 m
Explanation:
The definition of molality is:
molality = moles of solute / kg of solventFirst we calculate the moles of the solute, LiCl. We do so using its molar mass:
0.317 g ÷ 42.394 g/mol = 7.48x10⁻³ molThen we calculate the mass of the solvent, water. We do so using its density:
20.5 mL * 0.9982 g/mL = 20.5 g20.5 g / 1000 = 0.0205 kgFinally we calculate the molality of the solution:
7.48x10⁻³ mol / 0.0205 kg = 0.365 m383.2 K to degrees Celsius
Answer: 110.05
Explanation: i dont know i looked it up
How many molecules are contaiined in 125 grams of water, H2O?
Answer:
Water has a molar mass of 18.015 g/mol . This means that one mole of water molecules has a mass of 18.015 g . So, to sum this up, 6.022⋅1023 molecules of water will amount to 1 mole of water, which in turn will have a mass of 18.015 g . 2.7144moles H2O ⋅6.022⋅1023molec.
Explanation:
What happens to bromine on a molecular level when it is a gas but is then cooled to a liquid?
it is cooled to a liquid
Dogs and shrews are both members of this class:
O carnivora
O mammalia
O chordata
O canidae
What happens to matter that is used up during photosynthesis?
It retains its form and mass.
It retains its form but increases in mass.
It changes to a new form of matter with less mass.
It changes to a new form of matter with the same mass.
Answer:
I am almost positive that it is D. I might be incorrect do i appoligise if i am.
Explanation:
How many atoms are in 0.580 moles of CO2?
Answer:
[tex]1.05x10^{24}atoms[/tex]
Explanation:
Hello!
In this case, according to the definition of the Avogadro's number, it is possible to realize that one molecule of CO2 contains 3 moles of atoms, one of carbon and two of oxygen, thus, we have:
[tex]0.580molCO_2*\frac{3mol\ atoms}{1molCO_2} =1.74mol\ atoms[/tex]
Then, we use the Avogadro's number to obtain:
[tex]1.74mol\ atoms*\frac{6.022x10^{23}atoms}{1mol\ atoms} \\\\1.05x10^{24}atoms[/tex]
Best regards!
I need help with the bottom two pls The first answer I will mark brainliest
Answer:
I dunno, what is the answer
Explanation:
Part A
Summarize your research, and describe the attributes of the savanna.
Answer:
Savanna regions have two distinct seasons - a wet season and a dry season. There is very little rain in the dry season. In the wet season vegetation grows, including lush green grasses and wooded areas.
Savannas are grasslands found in Africa, Australia, South America, and India. The climate is warm or hot. Savannas experience both dry and rainy seasons. Each year, savannas receive about 20 to 50 inches of rain in a span of six to eight months. The other months are dryer. There’s also a threat of wildfires because of the severe dryness during these months. Grasslands are true to their name because their vegetation is mostly grass. Savannas are home to a wide range of animals, including different species of beetles and insects, which many creatures consume. Squirrels, mice, elephants, gazelles, and antelopes are the plant-eating animals that live in the savanna. Hyenas, lions, and leopards are some of the meat-eating animals in these areas. Some of the nonliving components of the system include very porous soil that allows water to drain easily.
True or false questions?
Most metal elements are brittle and do not conduct electricity. True or False
Any element can be identified by counting the protons in its neucleus. True or False
All Earths matter is made from the combination of about 100 elements. True or false
Answer:
1. False 2.True3.True? Unsure
Explanation:
Help me please (btw I live in the U.S)
Answer:
I live in the USA so the questions have been answered to reflect that accordingly.
1. The letter which represents summer where I live is Letter C
Explanation:
Letter C represents the June solstice which usually takes place between June 20 and June 21.
2. The letter which represents winter where I live is letter A.
Explanation:
Letter A represents the December solstice. Another name for this is Winter Solstice. This usually takes place in December for those living in the Northern Hemisphere like me. It is projected that this will take place on Tuesday, 21 December 2021.
Another name for this is Northern Hemisphere Winter Solstice as it marks the first day of winter.
3. The correct seasons for June Solstice are:
Northern Hemisphere: Summer Solstice
This projected to occur on Sunday, 20 of June 2020. It will be characterized by 1 hour of twilight and approximately 10 hours each of daylight and night time.
4. Southern Hemisphere: Summer solstice
This is anticipated on Tuesday, 21 December 2021. It will also be characterized by 1 hour of twilight and approximately 10 hours each of daylight and night time.
5. Northern Hemisphere: Autumnal (Fall) Equinox
6. Southern Hemisphere: Spring (Vernal) equinox
7. December Solstice - Northern Hemisphere: Winter Solstice is the Day of the Year with the shortest amount of sunlight
8. December Solstice - Southern Hemisphere: Summer Solstice. This is the day of the year with the longest amount of sunlight
9. March Equinox - Northern Hemisphere: Spring (Vernal) Equinox. This is the start of spring.
10. March Equinox - Southern Hemisphere: Autumnal (Fall) Equinox. This is the start of Fall.
Cheers!
what do you think will happen if there is no coal.
Answer:
If coal and petroleum will get exhausted it will be very difficult for us to transport because most vehicles depends on petroleum, Transport on Earth will became complicated, and if coal will get exhausted we will lose an unique fossil fuel. Coal is used in various domestic and industrial purposes.
Which upgrade to a school will most likely reduce the school's consumption of
nonrenewable resources?
Answer: if they use solar collection panels
Explanation:
How to get the density of this unknown liquid?
Answer:
Measure the volume of water poured into a graduated cylinder, then place the object in the water and remeasure the volume. The difference between the two volume measurements is the volume of the object. Now simply divide the mass by the volume to calculate the density of the object.
g A and B are both non-volatile molecular compounds. Substance A has a greater molar mass than substance B. If 50 g of substance A are dissolved in 250 g of water in one beaker, and 50 g of substance B are dissolved in 250 g of water in another beaker, then which ONE statement below will be true? A) the vapor pressure of solution A will be lower than the vapor pressure of solution B. B) the solution of A will freeze at a lower temperature than the solution of B. C) the two solutions will have the same vapor pressure. D) the boiling point of solution A will be lower than the boiling point of solution B. E) the solution of A will have a higher osmotic pressure than the solution of B.
Answer:
The correct answer is - option D. the boiling point of solution A will be lower than the boiling point of solution B
Explanation:
Colligative properties such as a decrease in the freezing point of the solution, increase in the boiling point of substance, decrease in Lowering of vapor pressure, and other properties depend upon the number of molecules only.
In the given solution the equal amount of two solutions are mixed that is 50 grams however due to the difference in the molecular mass so the atoms present in both solution A and B will be different. It is known that the number of atoms of a substance is inversely proportional to the molecular mass of the particular substance.
As it is given that Solution B has a low molecular mass which means it has a high number of atoms that means its boiling point will be higher than solution A.