Round to 4 significant figures.
35.5450
Answer:
35.55 to nearest 0.01 or
hundredth place
How many molecules are in 1.50 moles of hydrogen?
Answer:9.03*10^23
Explanation:
helpppp nowwww plsss!!
Answer:
A
Explanation:
if the earth slows down then that will give more time to the sun meaning days/nights will be longer
Copper roofs on houses form patina (copper carbonates) over the course of years due to the reaction with oxygen, carbon dioxide and water in the air. Which of the following statements is incorrect for this process?
A) The reaction has a low activation energy.
B) The reaction has a low reaction rate.
C) The formation of patina would occur faster during the summer than the winter.
D) The formation of patina would occur slower at higher altitudes due to lower concentration of reactant. E) Adding a catalyst would increase the rate of patina formation.
Answer:
The answer is "Choice A".
Explanation:
In this question, the choice A is wrong because when the copper panels on houses produce a patina (copper oxide) through occur as a consequence of reactions from oxygen and water in the air, these reaction does not have low activation energy because lower activation energy that is stored in a faster response rate.
Many factors would bring advantages when using fuel cells in cars but which factors present a drawback?
Answer:
B. hydrogen storage
Explanation:
Answer: B hydrogen storage
Explanation:
correct on edge 2020
Please help!!! Is the following example of synthesis? 2H2 + O2 —> 2H2O
Answer:
hahahaa i can get the points
Explanation:
yes it is again LOL thanks
Consider two reactants (A and B) that when mixed form a precipitate C, which can be filtered, dried, and then weighed. Carlos attempts to find the stoichiometric ratios in which A and B mix, by mixing different volumes of the same concentration of solutions of A and B (0.50 M). He records the following data:
Run Vol A (mL) Vol B (mL) Mass C (g)
1 10.0 10.0 1.17
2 20.0 10.0 2.33
3 30.0 10.0 3.50
4 40.0 10.0 3.50
Assuming that the products of the reaction are C and D, and that the stoichiometric coefficients for C and D are 1 and 2 respectively, the balanced chemical reaction will be
( ) A + ( ) B â 1 C + 2 D
Answer:
3A + B → C + 2D
Explanation:
Recall that:
[tex]\text{molarity} = \dfrac{no \ of \ moles}{volume \ of \ the \ solution}[/tex]
So;
[tex]\text{no \ of \ moles= molarity * volume \ of \ the \ solution}[/tex]
From the above table given in the question; we can have the following table:
Run moles of A moles of B Limiting reagent
1 0.5× 10⁻² 0.5× 10⁻² A and B are equal
2 1.0 0.5× 10⁻² 0.5× 10⁻² A
3. 1.5× 10⁻² 0.5× 10⁻² A
4 2.0× 10⁻² 0.5× 10⁻² B
Also, provided that the stoichiometric coefficients for C and D = 1 & 2 respectively.
Then, the stiochiometric ratio for A:B = [tex]\dfrac{1.5\times 10^{-2}}{0.5 \times 10^{-2}}[/tex]
[tex]= \dfrac{3}{1}[/tex]
Thus, the balanced equation is:
3A + B → C + 2D
In a reaction of iron and oxygen to produce iron (III) oxide, 12.5 grams of iron was consumed. The limiting reagent is ____ (compound) if 5.2 grams of oxygen was present. The theoretical yield (amount that is produced) is ____ (mass to the second decimal)
Blank 1:
Blank2:
Answer:
The limiting reagent is O₂ if 5.2 grams of oxygen was present. The theoretical yield is 17.25g of Fe₂O₃
Explanation:
The reaction is:
4Fe + 3O₂ → 2Fe₂O₃
We convert the mass of each reactant to moles:
12.5 g . 1mol / 55.85g = 0.224 moles of Fe
5.2g . 1 mol/ 32g = 0.1625 moles of oxygen.
We analyse the stoichiometry.
4 moles of Fe react to 3 moles of O₂
Then 0.224 moles of Fe will react to (0.224 . 3)/4 = 0.1678 moles of O₂
I need 0.1678 moles of O₂ and I only have 0.1625. Oxygen is the limiting reactant.
Now we go to the products:
3 moles of O₂ can produce 2 moles of Iron (III) oxyde
Then, 0.1625 moles of O₂ may produce (0.1625 . 2)/3 = 0.108 moles of Fe₂O₃
We convert the moles to mass:
0.108 mol . 159.7g /1mol = 17.25 g
Measurements show that unknown compound has the following composition: element mass 62.1 % carbon, 10.5 % hydrogen and 27.6 % oxygen. Write the empirical chemical formula of this compound?
Answer:
C3H6O
Explanation:
The percentage composition of the elements in the compound are given as follows:
62.1 % carbon = 62.1g of C
10.5 % hydrogen = 10.5g of H
27.6 % oxygen = 27.6g of O
Next, we convert each mass to mole by dividing by their molar/atomic mass
C = 62.1/12 = 5.175mol
H = 10.5/1 = 10.5mol
O = 27.6/16 = 1.725mol
Next, we divide each mole value by the smallest mole value (1.725)
C = 5.175mol ÷ 1.725 = 3
H = 10.5mol ÷ 1.725 = 6.086
O = 1.725mol ÷ 1.725 = 1
The empirical ratio approximately of C:H:O is 3:6:1, hence, the empirical formula is C3H6O
Explain the actinide contraction and its consequences
Answer:
Atomic and ionic size –
As the atomic number increases, the atomic size increases and effective nuclear charge also increases which attracts the outermost shell more effectively. So, as we move left to right means from actinium to lawrencium in the actinide series, there is gradual decrease in the the atomic or ionic radii with increase in atomic number. This steady decrease I atomic size is called actinide contraction. The actinide contraction is analog to the lanthanide contraction.
Cause of Actinide contraction –
The main reason of the actinide contraction is the imperfect shielding of the one 5f-electron by another 5f- electron in the same shell. Due to poor shielding effect of the 5f electrons, effective nuclear charge increases which causes the contraction in atomic size. When one electron is added to the 5f-orbital every time means proton keeps on increasing due to which the nuclear charge increases irregularly which causes the poor shielding effect.
CLICK THE WORD DOC AND IT WILL HAVE THE ANSWER
PLEASE MARK ME AS BRAINLIEST PLEASEEEEEEE
Account for the difference in the shape and color of the potential maps for ammonia and the ammonium ion.
Answer:
Explained below.
Explanation:
The difference between the two of them will be considered from their electrostatic potential maps.
First of all the major difference is that ammonia molecule(NH3) has a lone lone pair of electron on the N atom.
Due to the this lone pair of electron on the N - atom of ammonia, it's bond angle will be slightly lesser than that of ammonium ion.
Therefore, In the electrostatic potential map of NH3, the charge distribution will not be symmetrical for the fact that there is electron rich N atom and so the N atom will be more red than the 3 hydrogen atoms (H atoms).
Whereas, the electrostatic potential map of NH4+ (ammonium ion) will be symmetrical due to the even/symmetrical distribution of all the 4 hydrogen atoms surrounding the central Nitrogen atom.
Also, the Nitrogen atom here in ammonium ion will have a lower electron density than the Nitrogen atom that's present in ammonia molecule due to the bonding existing between the lone pair electron and the Hydrogen atom
Iron is a transition element. transition elements that make them different from non-transition metals
such as magnesium.
Answer:
Transition metals differ from the non-transition metals such as magnesium in the following ways;
They have variable oxidation statesFormation of complex ions.Formation of colored ions.Transition metals both in the elemental and compound forms can serve as catalysts.Explanation:
Transition elements comprise of those elements in the d-block of the periodic table and which have incompletely-filled d-orbitals.
The transition elements are all metals and has the characteristic physical properties of metals such as;
high melting and boiling points,good conductors of heat and electricity,metallic lusterhigh densitiesmalleability and ductilityHowever, their chemical properties differ from those of the non-transition metals such as magnesium in the following ways;
They have variable oxidation states - the transition metals exhibit variability in their oxidation states because of the close similarity in the energies of the 4s and 3d electrons which are available for bond formation. For example, while magnesium has only one oxidation state of +2, vanadium a transition metal can have oxidation states of +2, +3, +4 and +5.Formation of complex ions - A complex ion consists of a central metal atom or ion to which several other atoms, ions or molecules are bonded. For example, blue tetramine copper (ii) ion, [Cu(NH₃)]²⁺.Formation of colored ions - unlike non-transition metal ions, the ions of transition metals are usually colored. For example, Copper (ii) ions, Cu⁺ are blue, Chromium (ii) ions, Cr³⁺, are green, etc.Transition metals both in the elemental and compound forms can serve as catalysts. For example, finely divide nickel serves as a catalyst in the hydrogenation of vegetable oil to margarine, while vanadium (v) oxide serves as a catalyst in the contact process for the manufacture of tetraoxosulfate (i) acid.what is the mass of a gold bar with the following dimensions" 30 cm X 10 cm X 10 cm if the density of gold is 19.3g/cm^3?
Answer:
Volume of the bar=10 X 4 X 5=200 cm^3
Mass=200 X 19.3=3,860 grams
Mass=3.86 Kilograms
Explanation:
24. According to the author, the term avant-garde
most nearly means:
F. a particular art movement founded
internationally in the early 1900s.
G, a form of painting and sculpture
associated primarily with France.
H. art that is not the standard of the time.
J. art that has modernist roots.
the electron configuration of an element in its ground state is illustrated above. which, if any, of the three principles that determine the most stable electron configuration of an element does this configuration disobey
Answer:
hello your question is incomplete attached below is missing part
answer : Pauli's exclusion principle
Explanation:
The principle that was disobeyed is Pauli's exclusion principle this is because the Pauli's exclusion principle states that no two electrons can have the same set of quantum number.
In Box A the two electrons , have the same spin which means they have the same quantum number ( disobeys Pauli's exclusion principle )
Use stoichiometry to determine how many moles of O2 are needed
to completely react with 2.25 moles of C3H8. Please show your work
Answer:
11.25 moles of O₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
C₃H₈ + 5O₂ —> 3CO₂ + 4H₂O
From the balanced equation above,
1 mole of C₃H₈ reacted with 5 moles of O₂.
Finally, we shall determine the number of mole of O₂ needed to react with 2.25 moles of C₃H₈. This can be obtained as follow:
From the balanced equation above,
1 mole of C₃H₈ reacted with 5 moles of O₂.
Therefore, 2.25 moles of C₃H₈ will react with = 2.25 × 5 = 11.25 moles of O₂.
Thus, 11.25 moles of O₂ is needed for the reaction.
Describe how to calculate the Rf value for a spot on a TLC plate.
Answer:
In thin-layer chromatography, the retention factor (Rf) is used to compare and help identify compounds. The Rf value of a compound is equal to the distance traveled by the compound divided by the distance traveled by the solvent front (both measured from the origin).
HELP
NOW
Balance this equation: C2H5OH(1)+O2(g)—> CO2(g)+H2O(g)
Answer:
C2H5OH +O2(g)_CO2(g)+H2O(g) (unbalanced)
C2H5OH +3O2(g)_2CO2(g)+3H2O(balanced)
Consider the pair of solvolysis reactions. Draw the organic products, then predict the type of substitution mechanism and compare the expected rates.
Answer:
See explanation
Explanation:
Solvolysis is a chemical reaction in which the solvent, such as water or alcohol, is one of the reagents and is present in great excess of that required for the reaction. The solvents act as or produce electron-rich atoms or groups of atoms (nucleophiles) that displace an atom or group in the substrate molecule(Encyclopedia Britannica).
For the two reactions, the organic product is the same(the product is drawn in the second image attached). The both reactions occur by SN1 mechanism since the substrate is a tertiary alkyl halide. The nucleophile is CH3OH and the rate of reaction depends on the concentration of the alkyl halide and independent of the concentration of methanol present.
Therefore, changing the volume of the solvent has no effect on the rate of reaction. The two reactions proceed at exactly the same rate since the initial concentration of the alkyl halide is the same for both reactions.
How many total moles of ions are released when 0.0341 moles of Na2HPO4 dissolves completely in water
Answer:
0.1023 moles
Explanation:
We have this reaction
Na2HPO4 → 2Na+ + NPO4-
1 mole gives us 3 ions
Na+ has 2 ions to it
NPO4 has 1 ion
2 + 1 = 3
We multiply 3 with the number of moles to get the answer to this question
3 x 0.0341
= 0.1023 moles
So we conclude that total moles released when dissolved in water is equal to 0.1023
The mass % of C in methane (CH4) is?
Answer:
74.87% Carbon
Explanation:
The molecular mass of CH4 is 16.042 g/ mole.
X=(100 × 12.01) / 16.042= 74.87%
Answer:
[tex]\boxed {\boxed {\sf 74.87 \% \ C}}[/tex]
Explanation:
We want to find the mass percent composition of carbon in methane: CH₄
First, we must calculate the gram formula mass, also called the molar mass. Use the values for mass found on the Periodic Table. Look for carbon and hydrogen.
C: 12.011 gH: 1.008 gThere is no subscript after C, so there is just 1 atom. There is a subscript of 4 after H, so there are 4 atoms of hydrogen. We must multiply hydrogen's mass by 4.
C: 12.011 g H₄: 1.008 g * 4= 4.032 g CH₄= 12.011 g+ 4.032 g=16.043 gCalculate the percent composition.
[tex]\frac {mass \ of \ part}{mass \ of \ whole} *100[/tex]
The part is the carbon, or 12.011 grams.
The whole is the entire compound, CH₄, or 16.043 grams.
[tex]\frac { 12.011 \ g }{ 16.043 \ g} *100[/tex]
[tex]0.748675435*100\\74.8675435[/tex]
Let's round to the nearest hundredth. The 7 in the thousandth place tells us to round the 6 to a 7.
[tex]74.87 \% \ C[/tex]
The mass percent of carbon is 74.87%
Imagine that each of the three containers in Model 2 contains krypton atoms. The atomic radius of a krypton atom is 88.00 pm. Assuming the atom is a solid sphere, calculate the volume of one krypton atom in liters.
Answer:
The volume of a krypton atom in liters = 2.86 x 10⁻²⁷ liters
Explanation:
The volume of a sphere is given by the formula below:
V = 4/3 (π)(r³)
where π = 22/7, radius of the krypton atom = 88.00 pm
However, 1 picometre (pm) = 1 x 10⁻¹⁰ cm, converting 88.00 pm to cm will be:
88.00 pm x 10⁻¹⁰ cm/ 1 pm = 88.00 x 10⁻¹⁰ cm
Substituting the values above in order to determine the volume of a krypton atom:
V = 4/3 x (22/7) x (88.00 x 10⁻¹⁰ cm)³
V = 2.86 x 10⁻²⁴ cm³
However, 1000 cm³ = 1 liter
Therefore, 2.86 x 10⁻²⁴ cm³ in liters will be:
2.86 x 10⁻²⁴ cm³/ (1000 cm³/1 liter) = 2.86 x 10⁻²⁷ liters
The volume of a krypton atom in liters = 2.86 x 10⁻²⁷ liters
how many atoms are in 2.00 moles of Helium
Answer:
maybe try 4.002602, good luck
what is an animal that eats producers called?
Answer:
A consumer
Explanation:
Answer:
primary consumers
Explanation:
Dinitrogen tetraoxide is a colorless gas that dissociates into nitrogen dioxide, a reddish brown gas.
a. True
b. False
Answer:
False
Explanation:
Disassociation of Dinitrogen tetraoxide is shown below -
N2O4(g) ⇌ 2NO2(g)
Nitrogen dioxide gas is deep red-orange in color. However, in presence of aerosols, this gas appears reddish-brown in color.
Hence the given statement is False
A marshmallow is toasted over a campfire. Is this a physical or a chemical change?
Claim:
Evidence 1:
Reasoning 1:
Evidence 2:
Reasoning 2:
Answer:
Chemical Change
Explanation:
It is changeing color and taste
The toasting of marshmallows over a campfire is a chemical reaction.
What is a chemical change?A chemical change, often known as a chemical reaction, is the transformation of one or more components into new and distinct molecules or compounds.
Claim: When you toast marshmallows, the heat produces a chemical process that results in the formation of water molecules, which eventually evaporate, leaving carbon behind.
Evidence 1: The marshmallow become brown.Reasoning 1: When you toast sugar, it changes its chemical composition to form caramel, and the process is called caramelization.Evidence 2: The marshmallow melts.Reasoning 2: When the marshmallow is toasted, it melts down and becomes brown. This is a chemical change.Thus, these are the reasons why the toasting of marshmallows is a chemical change.
Learn more about chemical change, here:
https://brainly.com/question/1161517
5. Which diagram represents the alignment of the Earth, Moon and Sun during a spring
tide?
Answer:
the second one
Explanation:
I believe its thhe second one because isnt it when the earth is closest to the sun its winter.
i know its seems weird but that's what I learned
There are reasons for alignment. The second diagram represents the alignment of the Earth, Moon and Sun during a spring tide.
What is the alignment of the Earth moon and sun during a spring tide?Spring tides is known to often take place when the Earth, the Sun, and the Moon are said to be in one line.
This brings about a rise in the gravitational pull on the oceans. Few times, the Sun and Moon are known to be opposite sides of the Earth.
When you see the second diagram, you will see that they are on the same side and line.
Learn more about alignment of the Earth moon from
https://brainly.com/question/17255020
Which element would have similar properties to Sulfur? Chlorine O a ob Fluorine Oxygen Nitrogen
Answer:
sir/ma'am, i know i'm a NOOB at this kind of stuff but i believe it's oxygen.
Explanation:
i can't really remember the answer since it's been a week or so that i done this problem, it's between nitrogen and oxygen, though, i believe it's oxygen.
if ya don't believe me or trust me, then here's the link to help ya:
https://socratic.org/questions/what-elements-would-have-similar-properties-to-sulfur#628367
Decay chains exist because
C + O2 = CO2
If 12g of C reacts with 40g of O2, How much CO2 will be formed? State the law which governs your answer. (5 Mark)
PLEASE ANSWER FAST
Answer:
44 grams of CO₂ will be formed.
Explanation:
The balanced reaction is:
C + O₂ → CO₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:
C: 1 moleO₂: 1 moleCO₂: 1 moleBeing the molar mass of each compound:
C: 12 g/moleO₂: 32 g/moleCO₂: 44 g/moleBy stoichiometry the following mass quantities participate in the reaction:
C: 1 mole* 12 g/mole= 12 gO₂: 1 mole* 32 g/mole= 32 gCO₂: 1 mole* 44 g/mole= 44 gThe limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
If 12 grams of C react, by stoichiometry 32 grams of O₂ react. But you have 40 grams of O₂. Since more mass of O₂ is available than is necessary to react with 12 grams of C, carbon C is the limiting reagent.
Then by stoichiometry of the reaction, you can see that 12 grams of C form 44 grams of CO₂.
44 grams of CO₂ will be formed.