Answer:
A. When a piece of copper is heated, it combines with oxygen to form copper oxide. The chemical reaction for the same is as follows:
2 Cu (s) + O2(g) => 2CuO
B. The mass of the piece of copper will remain same and there will be no change in its mass. However, its volume will increase, so its density will decrease.
C. This is so because heating copper in its elemental form is a physical change and there is no change in mass during a physical change. Hence, the mass of copper remain same.
The net ionic equation for the dissolution of zinc metal in aqueous hydrobromic acid is ________.
Answer:
[tex]Zn(s)+2H^+(aq)\rightarrow Zn^{2+}(aq)+H_2(g)[/tex]
Explanation:
Hello!
In this case, since writing the net ionic equation implies the complete molecular equation, we should start by:
[tex]Zn(s)+2HBr(aq)\rightarrow ZnBr_2(aq)+H_2(g)[/tex]
Next, we represent the ionization of the aqueous species:
[tex]Zn(s)+2H^+(aq)+2Br^-(aq)\rightarrow Zn^{2+}(aq)+2Br^-(aq)+H_2(g)[/tex]
Whereas the spectator ions, those at both reactants and products are cancelled out so the net ionic equation is obtained:
[tex]Zn(s)+2H^+(aq)\rightarrow Zn^{2+}(aq)+H_2(g)[/tex]
Best regards!
Under conditions of constant temperature and amount of substance, a plot of pressure VS. volume for an ideal gas will result in:__________.
a) a line
b) a parabola
c) a logarithmic function
d) none of the above
Answer:
d) none of the above
Explanation:
The law that describes the relationship between pressure and volume of an ideal gas (under constant temperature and amount of substance) is Boyle's law.
It states that pressure is inversely proportional to the volume. This would mean that a graph of P vs 1/V would be a line.
See the attached picture for a graph of P vs V.
A plot of pressure VS. volume for an ideal gas will result in d) none of the above
The following things should be considered:
Boyle's law means the law that shows the relationship that lies between the pressure and volume of ideas gas that involved the same temperature and the substance amount.Also, the pressure should be inversly proportional with respect to the volume.Therefore we can conclude that a plot of pressure VS. volume for an ideal gas will result in d) none of the above
Learn more: brainly.com/question/23334479
I need these done please
Answer:
A, it is metal oxide
What is the mass of H2SO4 in a 38.2-cm3 sample of concentrated sulfuric acid that has a density of 1.84 g/cm3 and consists of 98.3% H2SO4
Answer:
69.09 g
Explanation:
First we calculate the mass of the sample of concentrated H₂SO₄, using the given volume and density:
Mass = density * volumeMass = 1.84 g/cm³ * 38.2 cm³ = 70.288 gThere are 70.288 grams of solution, of which 98.3% is H₂SO₄. Thus the H₂SO₄ mass is:
70.288 g * 98.3/100 = 69.09 gTaking into account the definition of density and percentage by mass, the mass of H₂SO₄ in a 38.2 cm³ sample of concentrated sulfuric acid is 69.09 grams.
Definition of densityBut first you must know the definition of density. Density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space.
In other words, density is a quantity that allows us to measure the amount of mass in a certain volume of a substance. Then, the expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:
[tex]density=\frac{mass}{volume}[/tex]
Mass of solutionIn this case, you know that:
Density= 1.84 [tex]\frac{g}{cm^{3} }[/tex]
Volume= 38.2 cm³
Replacing in the definition of density:
[tex]1.84 \frac{g}{cm^{3} }=\frac{mass}{38.2 cm^{3} }[/tex]
Solving:
mass= 1.84 [tex]\frac{g}{cm^{3} }[/tex]×38.2 cm³
mass= 70.288 g
So, the mass of the solution is 70.288 grams.
Definition of percentage by massThe percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.
In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.
The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:
[tex]percentage by mass=\frac{mass of solute}{mass of solution}x100[/tex]
Mass of H₂SO₄In this case, you know:
percentage by mass=98.3%
mass of solute= ?
mass of solution= 70.288 grams
Replacing in the definition of percentage by mass:
[tex]98.3=\frac{mass of solute}{70.288 grams}x100[/tex]
Solving:
[tex]\frac{98.3}{100} =\frac{mass of solute}{70.288 grams}[/tex]
[tex]0.983=\frac{mass of solute}{70.288 grams}[/tex]
0.983× 70.288 grams= mass of solute
69.09 grams= mass of solute
The mass of H₂SO₄ in a 38.2 cm³ sample of concentrated sulfuric acid is 69.09 grams.
Learn more about
density:
brainly.com/question/952755?referrer=searchResults
brainly.com/question/1462554?referrer=searchResults
percentage by mass:
brainly.com/question/18646836?referrer=searchResults
Calculate the molarity of the two solutions.
The first solution contains 0.350 mol of NaOH in 1.05 L of solution.
molarity:
The second solution contains 14.3 g of NaCl in 879 mL of solution.
molarity:
1. 0.33 M
2. 0.278 M
Further explanationMolarity is a way to express the concentration of the solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
[tex]\large{\boxed {\bold {M ~ = ~ \frac {n} {V}}}[/tex]
Where
M = Molarity
n = Number of moles of solute
V = Volume of solution
1. 0.350 mol of NaOH in 1.05 L of solution.
n=0.35
V=1.05 L
Molarity :
[tex]\tt M=\dfrac{0.35}{1.05}=0.33[/tex]
2. 14.3 g of NaCl in 879 mL of solution.
mol NaCl(MW=58.5 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{14.3~g}{58.5~g/mol}=0.244[/tex]
Molarity :
[tex]\tt M=\dfrac{0.244}{0.879~L}\\\\M=0.278[/tex]
What does it mean for a gene to be active?
Answer: You should be able to find the answer on the internet
What must be known for the rate constant to be calculated from the rate law?
A. The temperature at the beginning if the reaction
B. The reaction rate at known product concentrations
C. The reaction rate at known reaction concentrations
D. The activation energy the reaction must overcome
Answer:
C. The reaction rate at known reaction concentrations
Explanation:
The rate of a reaction is the measure of the speed of a chemical reaction. To find the rate constant of a reaction, the concentration of the reactants must be known.
Reaction rate is directly proportional to the concentration of the reactants. The quantitative relationship between the rate of a reaction and the concentrations of reactants is expressed as the rate law. From this we can deduce the rate constant.Answer:
C. ApE x Approved
Explanation:
Trust
Which of these elements has the highest first ionization energy?
a) As
b) Ga
c) Bi
d) Cs
e) K
Answer:
Cesium (Cs)
Explanation:
This eliment has an ionization energy of 3,8939
PLEASE HELP
This picture represents a model of:
Question 5 options:
Oxygen
Calcium
Boron
Neon
Answer:
The picture represents oxygen.
Explanation:
There are two notable ways you can figure this out:
1) Since there are eight protons, you can automatically know that you are looking for an element with an atomic number of 8. This is because the atomic number is the number of protons in an atom.
2) You can also note the number of electrons on the outer shell. These are called valence electrons. You can then see that the element has 6 valence electrons. Beginning with Lithium on the periodic table and count by ones going from left to right in period 2 of the periodic table until you get to 6. What element is that? It is indeed oxygen.
Answer:
Oxygen
Explanation:
Neons contain 8 protons and 10 ELECTRONS
Boron contains 5 protons an 5 electrons
calcium contains 20 electrons an 0 protons
pls help I I alot of HELP
Answer:
They need more oxhygen to fraction to incresse
Explanation:
In a climatological sense, dryness is a function of both annual rainfall and ________.
This a geology question.
Answer:
In a climatological sense, dryness is a function of both annual rainfall and evaporation
How can you increase the gravitational potential energy (GPE) of an empty shoe box on the middle shelf of a bookcase?
Answer:
Add Items to it
Explanation:
Lol I took the test. Sorry If I'm incorrect
Answer:
add items to the box to increase its mass on the self it is on
Explanation: :p
Help please! I’ll give brainliest!
Calculate the amount of heat required to completely sublime 96.0 gg of solid dry ice (CO2)(CO2) at its sublimation temperature. The heat of sublimation for carbon dioxide is 32.3 kJ/molkJ/mol. Express your answer in kilojoules.
Answer:
The correct answer is 70.41 kJ ≅ 70.4 kJ
Explanation:
The heat required to sublimate the solid at its sublimation temperature is calculated by using the following formula:
heat = ΔHs x moles of substance
Where ΔHs is the heat of sublimation, which is known (32.3 kJ/mol).
So, we have to calculate the moles of substance. For this, we can divide the mass of substance by the molecular weight of substance (CO₂):
mass CO₂ = 96.0 g
molecular weight CO₂ = (12 g/mol x 1) + (16 g/mol x 2) = 44 g/mol
⇒ moles of CO₂ = mass CO₂/molecular weight CO₂ = (96.0 g)/(44 g/mol) = 2.18 moles
Finally, we use the first formula to calculate the heat:
heat = ΔHs x moles = 32.3 kJ/mol x 2.18 mol = 70.41 kJ ≅ 70.4 kJ
A sample of gas occupies a volume of 571.5 mL at 0.944 atm and 10 oC. Determine the pressure of this sample at 1.183 L and 32 oC.
Answer:
0.491 atm
Explanation:
Initial volume V1 = 571.5 mL = 0.5715 L
Initial Pressure P1 = 0.944 atm
Initial Temperature T1 = 10 oC + 273 = 283 K (Converting to kelvin units)
Final Temperature T2 = 32 oC + 273 = 305K (Converting to kelvin units)
Final volume V2 = 1.183 L
Final Pressure P2 = ?
These parameters related by the combined gas law;
P1V1 / T1 = P2V2 / T2
Mke P2 subject of formular;
P2 = P1 V1 T2 / V2 T1
P2 = 0.944 * 0.5715 * 305 / 1.183 * 283
P2 = 0.491 atm
How do I cook eggs? Please tell me
17. Which of the following represent the correct net ionic equations from the double replacement reaction of
calcium nitrate and potassium phosphate?
a. Caaq) + PO43- (aq) → CaPO4(s)
b. Q Ca2+ (aq) + 3 PO43- (aq) → Caz(PO4)3(S)
c. 3 Ca2+ (aq) + 2 PO.3(aq) → Caz(PO4)2(S)
d. 2 NO3(aq) + Ca2+
+ Ca(NO3)2(S)
Answer:
D. 2 NO3(aq)+Ca2+
Explanation:
Reaction of calcium nitrate and potassium phosphate produce calcium phosphate and potassium nitrate. The net ionic equation for this is written as : [tex]3 Ca^{2+} (aq) +2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s)[/tex]. Thus option C is correct.
What is double displacement reaction?
In a double displacement reaction, two species or groups in reactant side are displaced in the products.
In a balanced chemical equation, all the reactants have to be in proper stochiometric ratio and the states of all species are mentioned in brackets.
In an ionic equation all the ions and charges are balanced both side and the number of each elements on both side too. The net ionic equation represents the formation of a solid product from its ions.
The balanced molecular equation and complete ionic equation are written for the given reaction below:
[tex]3 Ca (NO_{3})_{2} (aq)+ 2K_{3} PO_{4} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s) + 6 KNO_{3}(aq)[/tex]
[tex]3 Ca^{2+} (aq) +6 NO_{3}^{-} + (aq)+ 6K^{+} + (aq) 2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s) + 6 NO_{3}^{-} (aq)+ 6K^{+} (aq)[/tex]
Now when the same species on both side is cancelled, then the net ionic equation is written as:
[tex]3 Ca^{2+} (aq) +2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s)[/tex]
Therefore, the correct et ionic equation is option c.
To learn more about ionic equations, refer the link below:
https://brainly.com/question/15467511
#SPJ2
according to the big bang theory, which describes the universe before the actual big bang occurred?
Answer:
the answer is hot,dense points; each smaller than an atom
Explanation:
the big bang theory was proposed to suggest the expansion of the universe by describing the origin of all components of the universe and its planetary bodies. its suggested that the whole universe was in a state of high temperature and highly dense points (which were smaller than atoms) but continuously expanded by cooling down which gave rise to the formation of subatomic particles, atoms, etc.
btw I found this on brainly
You are asked to write observations about a 100g sample of Nitrogen-16 before it decays , but you running late. In order to make observations, you require at least 5g of material Can make observations you are 57 seconds late to the lab?
Answer:
You can not make the observation in the lab
Explanation:
We must know the amount of Nitrogen-16 that remains after 57 seconds before we can make our conclusion.
Hence, from;
N/No = (1/2)^t/t1/2
Where;
N = amount of Nitrogen-16 present after 57 seconds
No = 100g of Nitrogen-16 originally present
t = 57 seconds
t1/2 = half life of Nitrogen-16 which is 7.13 seconds
Substituting values;
N/100 = (1/2)57/7.13
N/ 100 =(1/2)^8
N/100 = 1/256
256N = 100
N = 100/256
N = 0.39 g
You can not make the observation because you need at least 5g of Nitrogen-16 and only 0.39 g is left after 57 seconds.
The minimum amount of sample required has been 5 grams, while the remaining sample has been 0.39 grams. Thus, it has not been possible to make the observations.
The half life can be defined as the time required for the sample to reduce to half of its initial concentration. The half life can be given as:
Amount remained = Initial amount [tex]\rm \times\;\dfrac{1}{2}^\dfrac{time}{Half-life}[/tex]
The half life of nitrogen 16 has been 7.13 second.
The initial concentration of the sample has been 100 grams.
The concentration of sample remained after 57 seconds has been:
Amount remained = 100 [tex]\rm \times\;\dfrac{1}{2}^\dfrac{57\;sec}{7.13\;sec}[/tex]
Amount remained = 0.39 grams.
The amount of sample remained after 57 seconds has been 0.39 grams.
The amount of sample required for the analysis has been 5 grams, after 57 seconds only 0.39 grams of sample has been remaining. Thus, the student will not be able to made analysis of nitrogen-16.
For more information about the sample decay, refer to the link:
https://brainly.com/question/1831303
Which of thes statements about heating up land and water is true
Answer:
b its radiant energy that heats up the earth.
Explanation:
Answer:
The answer is D
Explanation:
Heat from the Earth's core and radiation from the Sun is transferred to the surface of the Earth by conduction. The warm land and water radiates infrared, some of which is absorbed by the atmosphere, adding to its thermal energy.
which of the following is the best definition for volume
a. solids are the only matter with volume
b. all energy has volume
c. volume is the three-dimensional size of an object
d. gases do not have volume
Answer:
C
Explanation:
I hope that helps!!! it kinda gave you the answer though
A 1.00 g sample ofNH4N03 is decomposed in a bomb calorimeter. The temperature increases by 6.12 oc. What is the molar heat of decomposition of NH4N0.1
This question is incomplete, the complete question is;
A 1.00 g sample of NH4NO3 is decomposedin a bomb calorimeter. The temperature increases by 6.12°C. What is the molar heat of decomposition for ammonium nitrate?
Molar mass, NH4NO3 80.0 g/mol
Calorimeter Constant 1.23 kJ/°C
Answer:
the molar heat of decomposition for ammonium nitrate is - 602.4 kJ/mol
Explanation:
Given that;
change in temperature ΔT = 6.12 °C
Calorimeter Constant C = 1.23 kJ/°C
Molar mass, NH4NO3 = 80.0 g/mol
we know that;
Heat gained by the calorimeter (Q1) = Heat lost by the decomposition of NH4NO3 (Q2)
Q1 = C × ΔT
Q1 = (1.23 kJ/K) × (6.12 K) = 7.53 kJ
Q value we get becomes negative since we are talking about reaction and not calorimeter
hence
Q1 = - 7.53 kJ
now
1 g NH4NO3 decomposed, - 7.53 kJ of heat is released
so if 80 g which is 1 mol NH4NO3 decompose, the heat will be;
(80 g/mol x -7.53 kJ) / 1 g = - 602.4 kJ/mol
Therefore the molar heat of decomposition for ammonium nitrate is - 602.4 kJ/mol
does anyone know how to do this???
Answer:
2.9 g/cm³
Explanation:
From the question given above, the following data were obtained:
Mass = 236.376 g
Volume = 81.5 cm³
Density =?
Density can be defined as the mass of a substance per unit volume of the substance. It can be expressed mathematically as:
Density = mass /volume
With the above formula, we can obtain the density of the object as shown below:
Mass = 236.376 g
Volume = 81.5 cm³
Density =?
Density = mass /volume
Density = 236.376 / 81.5
Density = 2.9 g/cm³
Thus, the density of the object is 2.9 g/cm³
Sodium carbonate reacts with silver nitrate according to the following balanced equation: Na2CO3 (s) + 2 AgNO3 (aq) → Ag2CO3 (s) + 2 NaNO3 (9) If 3.60 g of Na2CO3 is allowed to react with 5.14 g of AgNO3, what mass of Na2CO3 will remain at the end of the reaction?
a) 2.01 g
b) 1.54 g
c) 0.423 g
d) 0.0150 g
e) 0g
Answer:
a) 2.01 g
Explanation:
Na₂CO₃ (s) + 2AgNO₃ (aq) → Ag₂CO₃ (s) + 2NaNO₃First we convert 0.0302 mol AgNO₃ to Na₂CO₃ moles, in order to calculate how many Na₂CO₃ moles reacted:
0.0302 mol AgNO₃ * [tex]\frac{1molNa_2CO_3}{2molAgNO_3}[/tex] = 0.0151 mol Na₂CO₃So the remaining Na₂CO₃ moles are:
0.0340 - 0.0151 = 0.0189 moles Na₂CO₃Finally we convert Na₂CO₃ moles into grams, using its molar mass:
0.0189 moles Na₂CO₃ * 106 g/mol = 2.003 g Na₂CO₃The closest answer is option a).
Which two factors often determine the type of rock that is formed by a process?
A.The type of material that is present at the beginning of the process
B.The amount of time the process of rock formation takes
C.The season in which the rock formation process ends
D.Whether the process takes place north or south of the equator
Answer:
A and B
Explanation:
Trust me I just did it on a p e x
Answer: he’s correct it’s d and b for me but it’s the same answers
Explanation:
hi lovessssssss
Hsnsgehsndgd
explain how to convert the moles to litters and litters to moles
Calculate the percent composition of Carbon in the
compound shown below. Record your answer with two
decimal places.
C18H18010
Answer:54.82%
Explanation:
Percentage of carbon = mass of carbon in that compound/ mass of the compund *100
216/394*100 = 54.82%
what is a biohazard?
Answer:
a risk to human health or the environment arising from biological work, especially with microorganisms.
Explanation:
Help! What is the the correct number for the product of this particular reaction?
Answer: synthesis, decomposition, single-displacement, double-displacement, combustion and acid-base reactions.
Explanation: