Answer:
An ice cube melting is a physical change because melting doesn't change the composition of the element. Paper burning is a chemical change because combustion occurs. Bubbles forming in a soda does involve chemical changes. Hard-boiling an egg is a chemical change because the egg's composition changed.
heyy guys, so basically i need help with stoichiometric calculation I will give you 100 points just to answer all of these answers accurately with working out (ps ill mark you brainliest x), thanks. PLEASE HELPPP. I'm desperate x
3. What masses of ethanol and ethanoic acid would need to be reacted together to give 1 g of ethyl ethanoate?
C^2H^5OH + CH^3CO^2 H → CH^3CO^2C^2H^5 + H^2O
4. What mass of iron(III) oxide would need to be reduced to produce 100 tonnes of iron in a blast furnace?
Fe^2^O^3 + CO → Fe + CO^2
5. What mass of silver nitrate as a solution in water would need to be added to 5 g of sodium chloride to
ensure complete precipitation of the chloride?
AgNO^3(aq) + NaCl (aq) → AgCl (s) + NaNO^3(aq)
6. Copper(II) oxide reacts with sulphuric acid to produce copper(II) sulphate. If this is allowed to crystallise the formula of the crystals is CuSO 4 .5H 2 O. What mass of copper oxide would be needed to produce 100 g of crystals?
CuO + H^2O + H^2SO^4 = CuSO^4 .5H^2O
7. In the following reactions calculate the mass of precipitate formed from 20 g of the metal salt in each case.
a. ZnSO^4 (aq) + 2NaOH → Zn(OH)^2(s) + Na^2SO^4(aq)
b. Al^2 (SO^4 ) 3(aq) + 6NaOH → 2Al(OH)^3(s) + 3Na^2SO^4(aq)
c. MgSO^4(aq) + 2NaOH → Mg(OH)^2(s) + Na^2^SO^4(aq)
Answer:
3. The mass of ethanol required is approximately 0.522869 g
The mass of ethanoic acid required is approximately 0.68156 g
4. The mass of iron (III) oxide required is approximately 285.952.189.095 tonnes
5. The mass of silver nitrate required is approximately 14.53 grams
6. The mass of copper oxide that would be needed is approximately 31.86 grams
7. a. The mass of the precipitate, Zn(OH)₂ formed is approximately 49.712 grams
b. The mass of the precipitate, Al(OH)₃ formed is approximately 13 grams
c. The mass of the precipitate, Mg(OH)₂, formed is approximately 14.579925 grams
Explanation:
3. The 1 mole of ethanol and 1 mole of ethanoic acid combines to form 1 mole of ethyl ethanoate
The number of moles of ethyl ethanoate in 1 gram of ethyl ethanoate, n = 1 g/(88.11 g/mol) = 1/88.11 moles
∴ The number of moles of ethanol = 1/88.11 moles
The number of moles of ethanoic acid = 1/88.11 moles
The mass of ethanol = (46.07 g/mol) × 1/88.11 moles = 0.522869 g
The mass of ethanoic acid in the reaction = 60.052 g/mol × 1/88.11 moles ≈ 0.68156 g
4. 1 mole of iron(III) oxide reacts with 1 mole of CO₂ to produce 1 mole of iron
The number of moles in 100 tonnes of iron= 100000000/55.845 = 1790670.60614 moles
The mass of iron (III) oxide required = 159.69 × 1790670.60614 = 285952189.095 g ≈ 285.952.189.095 tonnes
5. The number of moles of NaCl in 5 grams of NaCl = 5 g/58.44 g/mol = 0.0855578371 moles
The mass of silver nitrate required, m = 169.87 g/mol × 0.0855578371 moles ≈ 14.53 grams
6. The number of moles of CuSO₄·5H₂O in 100 g of CuSO₄·5H₂O = 100 g/(249.69 g/mol) ≈ 0.4005 moles
The mass of copper oxide required, m = 79.545 g/mol × 0.4005 moles ≈ 31.86 grams
7. a. The number of moles of NaOH in the reaction = 20 g/(39.997 g/mol) ≈ 0.5 moles
2 moles of NaOH produces 1 mole of Zn(OH)₂
0.5 moles of NaOH will produce 0.5 mole of Zn(OH)₂
The mass of 0.5 mole of Zn(OH)₂ = 0.5 mole × 99.424 g/mol = 49.712 grams
The mass of the precipitate, Zn(OH)₂ formed = 49.712 grams
b. 6 moles of NaOH produces 2 moles Al(OH)₃
20 g, or 0.5 mole of NaOH will produce (1/6) mole of Al(OH)₃
The mass of the precipitate, Al(OH)₃ formed, m = 78 g/mol×(1/6) moles = 13 grams
c. 2 moles of NaOH produces 1 mole of Mg(OH)₂, therefore;
20 g or 0.5 moles of NaOH formed (1/4) mole of Mg(OH)₂
The mass of the precipitate, Mg(OH)₂, formed, m = 58.3197 g/mol × (1/4) moles = 14.579925 grams
Answer:
Explanation:
i will show in details how 2 do the 1st Q n u can do the rest by following the way how it is done
3. given C^2H^5OH + CH^3CO^2H → CH^3CO^2C^2H^5 + H^2O
molar ratio of ethanol, ethanoic acid and ethyl ethanoate is 1 : 1 : 1
so mass = no. of moles * molecular mass
for same no. of moles, mass / molecular mass is the same
molecular mass of CH^3CO^2C^2H^5 = 12+1*3+12+16*2+12*2+5*1 = 88
molecular mass of C^2H^5OH = 12*2+1*5+16+1 = 46
molecular mass of CH^3CO^2H = 12+1*3+12+16*2+1 = 60
1 g of ethyl ethanoate = 1/88 mole
it requires 1/88*46 = 0.5227 g of ethanol; and
1/88*60 = 0.6818 g of ethanoic acid
to react together to form 1 g of ethyl ethanoate
Hydrogen gas (H2) is a promising alternative to fossil fuels. How many molecules are present in 1.0 kg of hydrogen gas
Answer:
3.01×10²⁶ molecules
Explanation:
From the question given above, the following data were obtained:
Mass of H₂ = 1 Kg
Number of molecules =?
From Avogadro's hypothesis,
1 mole of H₂ = 6.02×10²³ molecules
But 1 mole of H₂ = 2 × 1 = 2 g
Now, we shall determine the number of molecules present in 1 Kg (i.e 1000 g) of H₂ as follow:
From Avogadro's hypothesis,
2 g of H₂ = 6.02×10²³ molecules
Therefore,
1000 g of H₂ = 1000 × 6.02×10²³ / 2
1000 g of H₂ = 3.01×10²⁶ molecules
Thus, the number of molecules present in 1 Kg (i.e 1000 g) of H₂ is 3.01×10²⁶ molecules
How do you think the bonds between carbon atoms might be different in diamond and graphite?
Both have Giant Covalent Structures, resulting in very high melting temperatures. However each carbon atom in Diamond has 4 covalent bonds with other Carbons, making it extremely strong and hard. On the other hand, each carbon in graphite is bonded to three carbons, and therefore graphite is formed in layers.
Please help me with this activity!! I have to submit it ASAP. It's attached as a pdf. Not too long and for an Honors Electrons lesson.
(1) Seven electrons
1s² 2s²2p³
There are two electrons in the 2s subshell and three in the 2p subshell. The remaining two electrons are in the inner 1s subshell.
(2) 22 electrons
1s² 2s²2p⁶ 3s²3p⁶ 4s²3d²
There are two electrons in the 4s subshell and two in the 2p subshell. The remaining 18 electrons are in the inner subshells.
(3) 17 electrons
1s² 2s²2p⁶ 3s²3p⁵
There are two electrons in the 3s subshell and five in the 2p subshell. The remaining 10 electrons are in the inner subshells.
(4) n = 4, l = 2
(5) N=2 I=0 MI=0
(6) There can be two electrons in one orbital maximum. The s sublevel has just one orbital, so can contain 2 electrons max. The p sublevel has 3 orbitals, so can contain 6 electrons max. The d sublevel has 5 orbitals, so can contain 10 electrons max.
(7) n = 4 can hold up to 16 electrons
There are 4 sublevels; 42, 4p, 4d and 4f
4s (1 orbital), 4p (3 orbitals)
4d (5 orbitals), 4f (7 orbitals)
Maximum number of electrons in energy level: 16
s = 1 orbital
p = 3 orbitals
d = 5 orbitals
f = 7 orbitals
Add these up;
1 + 3 + 5 + 7 = 16
(8) 14 electrons If l = 3, the electrons are in an f subshell. The number of orbitals with a quantum number l is 2l + 1, so there are 2×3 + 1 = 7 f orbitals. Each orbital can hold two electrons, so the f subshell can hold 14 electrons.
sorry i didn't do the last two.. also sorry if some or none of these are correct, i tried my best
How long would it take Jesse, with an acceleration of -2.50 m/s², to bring his bicycle, with an initial velocity of 13.5 m/s, to a complete stop?
Answer:
i am so sorry. i do not have a answer but i am trying to find questioms i can answer
A balloon at sea level on earth (1 atm pressure, 19°C) takes up 14.5 L of space. The balloon travels to Mars where atmospheric pressure is 4.55 torr and the temperature is -55°C What is the volume of the balloon on Mars?
Answer:
1807.24L
Explanation:
Using combined gas law equation:
P1V1/T1 = P2V2/T2
Where;
P1 = pressure on Earth
P2 = Pressure on Mars
V1 = volume on Earth
V2 = volume on Mars
T1 = temperature on Earth
T2 = temperature on Mars
According to the information provided of the balloon in this question;
P1 = 1 atm
P2 = 4.55 torr = 4.55/760 = 0.00599atm
V1 = 14.5L
V2 = ?
T1 = 19°C = 19 + 273 = 292K
T2 = -55°C = -55 + 273 = 218K
Using P1V1/T1 = P2V2/T2
1 × 14.5/292 = 0.00599 × V2/218
14.5/292 = 0.00599V2/218
Cross multiply
14.5 × 218 = 292 × 0.00599V2
3161 = 1.74908V2
V2 = 3161 ÷ 1.74908
V2 = 1807.24L
Calculate the average atomic mass for element X
Answer:
39.02amu
Explanation:
According to this question, there are four (4) isotopes for element X with the following relative abundance:
Isotope 1 = 9.67%, mass no: 38
Isotope 2 = 78.68%, mass no: 39
Isotope 3 = 11.34%, mass no: 40
Isotope 4 = 0.31%, mass no: 41
To find the average atomic mass of element X, we multiply each isotopes' relative abundance by its mass no and find the sum as follows:
We convert each percentage to decimal abundance:
Isotope 1 = 9.67% = 0.0967
Isotope 2 = 78.68% = 0.7868
Isotope 3 = 11.34% = 0.1134
Isotope 4 = 0.31% = 0.0031
(0.0967 × 38) + (0.7868 × 39) + (0.1134 × 40) + (0.0031 × 41)
3.6746 + 30.6852 + 4.536 + 0.1271
Average atomic mass = 39.02amu
I need the answer to this asap!! please explain
Answer:
See explanation
Explanation:
Calcium carbide reacts with water to yield acetylene gas and calcium hydroxide as follows;
CaC2(s)+2H2O(g)⇋Ca(OH)2(s)+C2H2(g)
This now shows us that the equation as written in the question is wrong. Since the equation for the reaction of calcium carbide and water as shown in the question is wrong, the equation can not be balanced.
What do we need in order to obtain energy?
Explanation:
hope it helps thanks ❤
brainliest please
Answer:
Explanation:
human obtains energy by eating food. as food is digested n broken down in our digestive system, energy is released to our body.
Under which conditions is a reaction spontaneous?Edmentum.
Answer:
When ΔS > 0 and ΔH < 0, the process is always spontaneous as written. When ΔS < 0 and ΔH > 0, the process is never spontaneous, but the reverse process is always spontaneous. When ΔS > 0 and ΔH > 0, the process will be spontaneous at
Explanation:
What are the best conditions to lead towards a spontaneous reaction? high negative enthalpy, high temp, high positive entropy. Your enthalpy is high and negative but your entropy is also negative.
give me a fully balanced equation of lead monoxide and nitric acid
Answer:
Explanation:
Lead Monoxide: PbO
Nitric Acid: HNO3
PbO + 2 HNO3 ---> Pb(NO3)2 + H2O
Answer:
Explanation:
mono mean single so lead monoxide is PbO
nitric acid is HNO3
both Pb n O are double-charged while H n NO3 are single
so balanced eqn is:
PbO + 2HNO3 -> Pb(NO3)2 + H2O
Put these atoms in order from most negative overall charge to least negative
overall charge.
11 Atom X: 104 protons, 102 electrons
11 Atom B: 24 protons, 18 electrons
1 Atom Q: 15 protons, 16 electrons
11. Atom P: 7 protons, 10 electrons
Answer:
3 Protons, 2 Neutrons, & 3 Electrons. Is the charge of this atom positive, negative, or neutral?
Explanation:
Put these atoms in order from most negative overall charge to least negative
overall charge.
11 Atom X: 104 protons, 102 electrons
11 Atom B: 24 protons, 18 electrons
1 Atom Q: 15 protons, 16 electrons
11. Atom P: 7 protons, 10 electrons
what is the wave speed
a wave with a wave length of 1000 m and a frequancy of 3000000 Hz
Answer:
v = 3,000,000,000 m/s
Explanation:
v = f *L
v = 3,000,000 * 1000
v = 3,000,000,000 m/s
what is the difference between physical chemistry and environmental chemistry.
please Answer and give the correct answer...
Answer:
Physical chemistry is the study of macroscopic, and particulate phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibrium while environmental chemistry is the study of chemical processes that occur in water, air, terrestrial and living environments, and the effects of human activity on them.
Physical chemistry is the area of chemistry that deals with how materials interact and change. The scientific study of chemical and biological phenomena that take place in the environment is known as environmental chemistry.
Physical chemistry attempts to quantify, correlate, and explain the quantitative features of reactions by focusing, in contrast to other branches, on the physics principles that underlie all chemical interactions (such as the gas laws).
While environmental chemistry is the study of chemical species' sources, reactions, movement, impacts, and fates in the air, soil, and water environments, as well as the impact of human activity and biological activity on these, can be summed up as the field of chemical ecology.
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https://brainly.com/question/22517940
The reaction below shows how the potential energy changes during a phase
change. What does the red arrow show?
Potential Energy
Reaction Progress
A. The change in enthalpy is positive, and the reaction is
endothermic.
B. The change in enthalpy is negative, and the reaction is exothermic.
C. The activation energy is negative, and the reaction is exothermic.
D. The activation energy is positive, and the reaction is endothermic.
Answer:
the red arrow shows that the change in enthalpy is positive
From the energy diagram, it is clear that, the enthalpy of the reaction is positive and it is an endothermic reaction.
What is an endothermic reaction ?An endothermic reaction is a chemical reaction that absorbs heat from its surroundings, resulting in a decrease in temperature of the surroundings. In other words, energy is taken in by the reaction from the environment.
During an endothermic reaction, the reactants absorb energy in the form of heat, light, or electricity to break the bonds between their atoms and form new bonds to create products.
The amount of energy absorbed by the reactants is greater than the energy released by the products. This energy difference is usually expressed as the enthalpy change (∆H) of the reaction, which is positive for endothermic reactions.
Here, the energy of products is higher than that of reactants and hence option A is correct.
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A gas is put into a cosed container.
The container and the gas inside it are heated.
What will happen to the pressure inside the container?
Answer:
When gases in containers are heated, their molecules increase in average speed. This means that they exert a greater force when they collide with the container walls, and also collide with the walls more frequently. The gas is therefore under greater pressure when its temperature is higher.
the stomach, small intestine, and large intestine are all organs. when they work together to process food, they form a functional unit known as
Answer:
Organ System
Explanation:
These organs are helping each other process food and therefore be an Organ System
Why is it essential for a calorimetry to be an insulated (closed) system?
A. The heat exchange must originate from only the reaction (system).
B. Thermal insulation minimizes energy loses to the atmosphere.
C. A and B
D. None of the Above
Answer:
B.Thermal insulation minimizes energy loses to the atmosphere.
Explanation:
It is important because it helps to stop hit from transferring from the calorimeter to the environment. This would help to have an accurate measurement of the heat that was used in the chemical process. The greatest cause of error that happens in calorimetry is when heat is lost to the environment. To reduce this, you insulate the calorimeter and add a cover.
(6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol)) - (1 mol)(-1,273.02 kJ/mol)= ?kj
Answer:
-2,802.960 kJ
Explanation:
The dimensional equation of the given quantities is presented as follows;
(6 mol) × (-393.5 kJ/mol) + (6 mol) × (-285.83 kJ/mol) - (1 mol) × (-1,273.02 kJ/mol) = ? kJ
The equation, can be written as follows;
[tex]\left (6 \times (-393.5) \, mol \times \dfrac{kJ}{mol} \right ) + \left(6 \times (-285.83) \, mol \times \dfrac{kJ}{mol} \right) - \left (1 \times (-1,273.02) \, mol \times \dfrac{kJ}{mol} \right) = ?[/tex]We note that [tex]mol \times \dfrac{kJ}{mol} \right) = kJ[/tex], therefore, the above equation becomes;
[tex]\left (6 \times (-393.5) \ kJ\right ) + \left(6 \times (-285.83) \ kJ \right) - \left (1 \, \times (-1,273.02) \ kJ \right) = -2,802.960 kJ[/tex]
Answer:
C. ((6 mol)(-393.5 kJ/mol) + (6 mol)(-285.83 kJ/mol)) - (1 mol)(-1,273.02 kJ/mol)
Explanation:
Got it right on edge.
: the one after is -2803.
What is the HCPCS Level II code for the compounded concentrated form of 0.5 mg Levalbuterol HCL when inhaled
Answer:
aefhfcjd
Explanation:
How many moles of water vapor are formed. when 10 litres of butane gas c4h10 is burned in oxygen at STP
Using the idea of the molar volume of butane gas, we have 2.23 moles of water vapor.
What is a reaction equation?The term reaction equation shows the conversion of reactants to products. First of all, we must get down the reaction equation as follows;
C4H10(g) + 13/2O2(g) ----> 4CO2 (g) + 5H2O(g)
From the balanced reaction equation;
1 mole of butane gas yields 5 moles of water vapor. Since 1 mole of butane gas occupies 22.4 L. Hence;
22.4 L of butane yields 5 moles of water vapor
10 L of butane gas yields 10 L * 5 moles/22.4 L = 2.23 moles
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please let me know if this is correct?
Answer: Yes! you're all good. Alkali metals in group 1 are the most metallic :)
Ecstasy is one example of which of the following?
Depressants
Narcotics
O Club drugs
Stimulants
Answer:
Narcotics
I think ans is
Explanation:
tropicaia
Ecstasy, also known as MDMA, is used recreationally, so it can be called a club drug. However, it is illegal in the US, so it would be considered a narcotic as well. The effects it has are also of the stimulant variety, so they would fall under that category as well. It is definitely not a depressant.
_______organisma consist of only one cell and _________ organisms consist of many cells
Answer:
Unicellular organisms consist of only one cell and multicellular organisms consist of many cell.
Explanation:
Living things made up of a cell are called unicellular beings. They are very small and simple. In other words, unicellular organisms are those that are formed only by a single cell in which all the vital functions necessary for life are produced. For this reason, they are mostly microscopic organisms. Examples of unicellular organisms are viruses or bacteria.
Multicellular organisms are made up of a large number of cells. They present, therefore, a greater complexity than unicellular organisms in terms of the functions they develop. All current multicellular organisms come from a single cell, that is, they begin their life being unicellular. That is, they are formed from a zygote. Some examples of multicellular organisms are mammals, fungi, and mosses.
So, unicellular organisms consist of only one cell and multicellular organisms consist of many cell.
Balance the equation
__Cu+__Ag(NO3)——__Cu(NO3)2+__Ag
Balanced chemical equation for above reaction :
[tex] \mathrm{Cu +2 \: AgNO_3 \longrightarrow Cu(NO_3)_2 + 2 \: Ag}[/tex]
This is a displacement reaction, where copper (Cu) being morereactive than Silver (Ag) displaces Silver from its compound " Silver Nitrate " to form " Copper Nitrate " and silver .
[tex]\mathrm{✌TeeNForeveR✌}[/tex]
Which statement correctly describes a product of a reaction within
photosynthesis?
O A. ATP is produced during the light reactions.
O B. Carbon dioxide is produced during the light reactions.
O C. Oxygen is produced during the Calvin cycle.
OD. NADPH is produced during the Calvin cycle.
Answer:
B
pls correct me if im wrong
What are the values of the solute amount in moles and the solution volume in liters.
Answer:
0.250L of solution. 0.250 moles of solute.
Explanation:
As you can see in the image, there is a beaker with an amount of solution. 1/2L are 500mL and each line of the beaker represents 100mL. That means the volume of the solution is approximately 250mL = 0.250L
Molarity is an unit of concentration defined as the moles of solute per liter of solution. A solution that is 1.000M contains 1.000 moles of solute per liter of solution.
As the volume of the solution is 0.250L, the moles are:
0.250L * (1.000mol/L) = 0.250 moles of solute
Viruses are called obligatory parasites. Why
Viruses are known as obligatory parasites as they only become active and multiply when inside a host. Viruses are inactive when they are outside.
write your 5 ways how to you can help earth
Answer:
any 5 ways to prevent earth are:
1.using ( 3R) principles Reduce, reuse, and recycle.
2.Educate yourself
3.Conserve water resources and other natural resources
4.Use long-lasting light bulbs.
5.stop deforestation and start afforestaion
All light waves can be described in terms of their speed, frequency, and_____