Answer:
9.5 hours/ 9 hours 30 mins
Explanation:
Distance = speed × time so
Time = Distance ÷ speed
= 570 ÷ 60
= 9.5 hours
which of the following pairs are ionic compounds ( Al,Cl),(Na,O),(Al,F)
Answer:
This answer I think it is Al,F
equator runs east and west all the way around the world,halfway between the south poles called the ______________and north poles called________________.
now na po plss....
then follow me☝
Answer:
hanigin ng mga pule natin
Diamond is an allotrope of :
a. carbon b. sillica
c. phosphorus c. Nitrogen
Answer:
carbon
Explanation:
because it is an allotrope of carbon
Answer:
Carbon
Explanation:
its literaly carbon
Which of these will form hydrogen bonds? a. CH2Br2 b. CH3OCH2CH3 c. H2NCH2COOH d. H2SO3 e. CH3CH2OH
Answer:
Which of these will form hydrogen bonds?
a. CH2Br2
b. CH3OCH2CH3
c. H2NCH2COOH
d. H2SO3
e. CH3CH2OH
Explanation:
A hydrogen bond is the weak electrostatic force of attraction that exists between a covalently bonded hydrogen atom and a highly electronegative atom like N,O, and F.
For example, water has a hydrogen bond between the hydrogen atoms of one molecule and the oxygen atom of another molecule.
Among the given molecules,
a. CH2Br2 does not have a hydrogen bond because it does not have N or O or F.
b. CH3OCH2CH3 does not have a hydrogen bond.
Due to the absence of -OH or -NH or H-F bonds.
c. H2NCH2COOH shows hydrogen bonding.
d. H2SO3 has hydrogen bonding.
Due to the presence of -OH bond.
e. CH3CH2OH has hydrogen bonding.
Due to the presence of -OH bond.
plant growth is chemical change or physical change
Answer:
its a chemical change.
hope it helps.
stay safe healthy and happy...Answer: it is a chemical change because it involves chemical process
Explanation:
What are the basic elements of selection of proffesion?describe any two
Answer:
overall I think one answer
the molar mass of oxygen(O2) is 32g. what is the mass of 1.05*10^25 molecules of O2
Answer:
3.36×10²⁶ g
Explanation:
Molar mass ( O2) = 32g/mol
mole(O2) = 1.05×10²⁵mol
Mass(O2) = ?
mole(n)= mass(m)/Molar mass(M)
n×M = m
1.05×10²⁵ mol × 32g/mol = mass
mass= 3.36×10²⁶ g
2. Find the slope of the line that passes between the points (12,5) and (2,3).
Write your formula for Slope
m=y2 −y1/x2-x1
Explanation:
3-5/2-12=1/5
A mechanical wave starts when matter is disturbed by a source
of_______ I NEED ANSWER ASAP
Answer:
i believe energy is your answer here
How to work out the amount of carbon dioxide that is released when fully combusted with 4kg of ethanol?
Answer:
There is 7642 grams of CO2 released
Explanation:
Step 1: Data given
carbon dioxide = CO2
Molar mass of carbon dioxide = 44.01 g/mol
Mass of ethanol = 4 kg = 4000 grams
Molar mass of ethanol = 46.07 g/mol
Step 2: The reaction
Combustion of ethanol means there is oxygen (O2) added. The products are CO2 and H2O.
C2H5OH + 3O2 → 2CO2 + 3H2O
Step 3: Calculate number of moles of ethanol
Moles ethanol = mass ethanol / molar mass ethanol
Moles ethanol = 4000 grams / 46.07 g/mol
Moles ethanol = 86.82 moles
Step 4: Calculate number of moles CO2
For 1 mol ethanol we need 3 moles to produce 2 moles CO2 and 3 moles H2O
For 86.82 moles of ethanol we'll have 2*86.82 = 173.64 moles CO2
Step 5: Calculate mass of CO2
Mass CO2 = moles CO2 * molar mass CO2
Mass CO2 = 173.64 moles * 44.01 g/mol
Mass CO2 = 7642 grams
There is 7642 grams of CO2 released
Zinc oxide + carbon =
Answer:
carbondioxe and zinc as solid
An iron block of mass 18 kg is heated from 285 K to 318 K. If 267.3 kJ is required, what is the specific heat of iron?
A. 490.05
B. 158.77
C. 145.80
D. 450.00
Answer:
D. 450 J/kgK
Explanation:
Using the formula as follows:
Q = m × c × ∆T
Where:
Q = amount of heat absorbed/released (J)
m = mass of substance (g)
c = specific heat capacity
∆T = change in temperature (°C)
According to the information provided in this question:
Q = 267.3 kJ = 267300J
m = 18kg
∆T = 318K - 285K = 33K
c = ?
Q = m × c × ∆T
c = Q ÷ m∆T
c = 267300 ÷ 18 × 33
c = 267300 ÷ 594
c = 450 J/kgK
Which describes the difference between a claim and a scientific claim?
Claims are based more on truth than scientific claims are.
Anyone can make a claim, but a scientific claim is backed by experimental evidence.
Claims are based on evidence and scientific claims are made by scientists.
Controlled experiments are used in claims, while scientific claims use multiple trials.
Answer:
B. Anyone can make a claim, but a scientific claim is backed by experimental evidence.
<3 Have a nice day!!
Answer:
the awnser is B i got it right
Explanation:
Which of the following statements regarding diffusion is false? Group of answer choices Diffusion is a result of the thermal energy of atoms and molecules. Diffusion occurs even after equilibrium is reached and no net change is apparent. Diffusion requires no input of energy into the system. Diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated.
Answer: The statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.
Explanation:
When particles or atoms of a substance are able to move rapidly from one place to another then it is called diffusion.
During diffusion, particles tend to move apart from each other.
For example, spreading of dye molecules into water.
Thus, we can conclude that the statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.
What is the basic difference between exergonic and endergonic reactions? Group of answer choices Exergonic reactions release energy; endergonic reactions absorb it. Exergonic reactions involve ionic bonds; endergonic reactions involve covalent bonds. Exergonic reactions involve the breaking of bonds; endergonic reactions involve the formation of bonds. In exergonic reactions, the reactants have less chemical energy than the products; in endergonic reactions, the opposite is true.
Answer: the basic difference is Exergonic reactions release energy and an endergonic reactions absorb energy .
HOPE THIS HELPS!!!
Please can someone answer quickly this do tomorrow morning
Which of the five signs should not be used by themselves?
Precipitate
Temperature change
Color change
Odor
Bubbles
Temperature change
Pls corret my answer if its wrong ●~●#CarryOnLearningIn the hydrogenation of double bonds, a catalyst is needed. In the third step, the reactants react to form the product. This step is known as
Answer:
reaction
Explanation:
A reaction is defined as a process where the chemical transformation takes place from one form to some other form. Here, two different chemical substances are reacted together to form some other completely different product.
A hydrogenation process is a chemical process where between the molecular hydrogen and some another element or a compound. This process is usually carried out in the presence of catalyst mainly nickel, platinum or palladium.
Thus, in hydrogenation of a double bond, the catalyst is used to speed up the reaction. The first step in this process is adsorption process, the second step is the diffusion process, the third step is the reaction process and the last step is the desorption process.
Which statement about biogeochemical cycles is true?
O A. Plants are a part of the nitrogen and carbon cycles, but not the
water cycle.
O B. Plants are a part of the nitrogen, carbon, and water cycles.
O c. Plants are a part of the water and carbon cycles, but not the
nitrogen cycle.
D. Plants are a part
carbon cycle.
the water and nitrogen cycles, but not the
Answer: The answer is D:
Answer:
The answer is Option D
Which has more mass, 2 kg of steel or 5 kg of feather.
Answer:
5 kg of feather
Explanation:
alguien que me pase una pagina para mirar nopor
Answer:
no pues nadie te pasa la pagina
Suggest two ways Becky could make tea dissolve more quickly
NO FIlES OR REPORTED
Answer:
heat mixture/stir
Explanation:
these are factors of dissolving of solvent faster
True or false, If an atom is charged negative, it contains more electrons than protons.
Answer:
True
Explanation:
An atom would carry more protons if positively charged, an equal amount of both protons and electrons if neutral, and more electrons if charged negative.
This is the chemical formula for calcium phosphate:
Ca3PO42.
Calculate the mass percent of oxygen in calcium phosphate. Round your answer to the nearest percentage
Answer:
This is the chemical formula for calcium phosphate:
[tex]Ca_3(PO_4)_2[/tex].
Calculate the mass percent of oxygen in calcium phosphate. Round your answer to the nearest percentage
Explanation:
The molar mass of calcium phosphate is: 310.18g/mol.
In one mole of calcium phosphate there are 8 moles of oxygen atoms.
The atomic mass of oxygen in calcium phosphate is: 128.0 g
Hence, the mass % of oxygen in the given compound is:
[tex]mass% of Oxygen =\frac{mass of oxygen}{mass of calcium phosphate}*100\\&=\frac{128.0g}{310.18g} *100\\&=41.3[/tex]
Hence,mass%of oxygen is 41.3.
what is the formulas for Calcium Chloride,Aluminium Sulphate and Sodium hydroxide. *
Answer:
Explanation:
Why is there a star * behind the question.
CaCl2
Al2(SO4)3
NaOH
It is known that oxygen contains 1 percent of the air. If 50 liters of wind, how much oxygen is needed?
Answer:
Amount of oxygen needed is 5,000 liter
Explanation:
Given:
Percent of air in oxygen = 1%
Find:
Oxygen if 50 liter of wind
Computation:
Oxygen if 50 liter of wind = 50 liter wind[100% / 1% ]
Oxygen if 50 liter of wind = 50 liter wind[100]
Oxygen if 50 liter of wind = 50[100]
Oxygen if 50 liter of wind = 5,000
So,
Amount of oxygen needed is 5,000 liter
If a man reach a 25 km distance in 30 min in his car , find the average velocity
Answer:
Average velocity of car = 50 km/h
Explanation:
Given information;
Distance cover by man in his car = 25 kilometer
Time taken by man to cover distance = 30 min
Find:
Average velocity of car
Computation:
Time taken by man to cover distance = 30 min
Time taken by man to cover distance = 30 / 60
Time taken by man to cover distance = 0.5 hour
Average velocity = Distance / Time
Average velocity of car = Distance cover by man in his car / Time taken by man to cover distance
Average velocity of car = 25 / 0.5
Average velocity of car = 50 km/h
The normal boiling point of ethanol is 78.4 oC. Its enthalpy of vaporization is 38.6 kJ/mol. Estimate the vapor pressure of ethanol at 26.3 oC.
Answer: The vapor pressure of ethanol at [tex]26.3^{o}C[/tex] is 238.3 torr.
Explanation:
Given: [tex]\Delta H_{vap}[/tex] = 38.6 kJ/mol
[tex]T_{1} = 26.3^{o}C = (26.3 + 273) K = 299.3 K[/tex]
[tex]T_{2} = 78.4^{o}C = (78.4 + 273) K = 351.4 K[/tex]
Formula used to calculate the vapor pressure of ethanol is as follows.
[tex]ln\frac{P_{2}}{P_{1}} = \frac{\Delta H_{vap}}{R} [\frac{1}{T_{1}} - \frac{1}{T_{2}}]\\[/tex]
Substitute the values into above formula as follows.
[tex]ln\frac{P_{2}}{P_{1}} = \frac{\Delta H_{vap}}{R} [\frac{1}{T_{1}} - \frac{1}{T_{2}}]\\ \\ln \frac{760 torr}{P_{1}} = \frac{38600 J}{8.314 J/mol K}[\frac{1}{299.3} - \frac{1}{351.4}]\\\frac{760}{P_{1}} = 3.18\\P_{1} = 238.3 torr[/tex]
Thus, we can conclude that the vapor pressure of ethanol at [tex]26.3^{o}C[/tex] is 238.3 torr.
Wood is made mostly of cellulose and has a chemical formula of C.H.00. Which of the following equations
represents the cellulose combustion reaction?
Answer:
Option B.
C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O
Explanation:
To know which option is correct, we shall write the balanced equation for the combustion of cellulose. This is illustrated below:
C₆H₁₀O₅ + O₂ —> CO₂ + H₂O
There are 6 atoms of C on the left side and 1 atom on the right side. It can be balance by writing 6 before CO₂ as shown below:
C₆H₁₀O₅ + O₂ —> 6CO₂ + H₂O
There are 10 atoms of H on the left side and 2 atoms on the right side. It can be balance by writing 5 before H₂O as shown below:
C₆H₁₀O₅ + O₂ —> 6CO₂ + 5H₂O
There are a total of 7 atoms of O on the left side and a total of 17 atoms on the right side. It can be balance by writing 6 before O₂ as shown below:
C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O
Now, the equation is balanced.
Thus, option B gives the correct answer to the question.
For a reaction, AH = 176 kJ/mol and A SO = 0.285 kJ/(K•mol). At what
temperatures is this reaction spontaneous?
A. At no temperature
B. T< 50 K
C. T>617 K
D. T< 617 K
Answer:
C. T>617 K
Explanation:
We are given that
[tex]\Delta H=176KJ/mol[/tex]
[tex]\Delta S=0.285KJ/K\cdot mol[/tex]
We have to find the temperature at which the reaction is spontaneous.
When
[tex]\Delta H>0, \Delta S>0[/tex]
Therefore, the reaction is spontaneous at certain range of temperature.
Option A is not true.
[tex]\Delta G=\Delta H-T\Delta S[/tex]
When [tex]\Delta G[/tex] is negative, then the reaction is spontaneous.
[tex]\Delta G=176-0.285T[/tex]
When T<50
Suppose T=49 K
[tex]\Delta G=176-49\times 0.285>0[/tex]
Therefore, [tex]\Delta G is positive[/tex].Hence, the reaction is not spontaneous.
Option B is wrong.
C.T>617K
Suppose T=618 K
[tex]\Delta G=176-0.285\times 618=-0.13<0[/tex]
Therefore, [tex]\Delta G is negative[/tex].Hence, the reaction is spontaneous.
So, option C is true.
D.T<617 K
Suppose T=616 K
[tex]\Delta G=176-0.285\times 616=0.44>0[/tex]
Therefore, [tex]\Delta G is positive[/tex].Hence, the reaction is not spontaneous.
So, option D is not true.
¿Qué características distinguen a los coloides de otras mezclas?
