Guys please help me i will mark brainly!
Answer:
D
Explanation:
Copper has a specific heat of 0,900 J(g C). How much energy in kJ is needed to raise the temperature of a 700 g block of aluminum from 30.7°C to 82,1C?(show your steps)
Answer:
32.4 kJ
Explanation:
Given that:
Specific heat capacity fo copper, c = 0.9
Mass of copper, m = 700 g
Temperature change, dθ ;t2 - t1 = (82.1 - 30.7) = 51.4
Energy required, E = mcdθ
E = 700 * 0.9 * 51.4
E = 32382 J
Energy required on kJ
32382 / 1000
= 32.382 kJ
= 32.4 kJ
How many grams equal 4.3 x 1024 atoms of oxygen (02)?
Answer: 248.66g
Explanation:
4.3e24 / 6.23e23 = 6.9 mols O2
6.9(18.02*2)=248.66
how many moles of nitrogen gas are produced in the reaction if we started with 6 moles of ammonium nitrate
adaptive features of aquatic plants
Whoever gets these 2 right gets brainliest! :)
the first one is A covalent bond.
the second one is Answer: B Decomposition
A student plans a two-step synthesis of 1-ethyl-3-nitrobenzene from benzene. The first step is nitration of benzene to give nitrobenzene, and the second step is a Friedel-Crafts alkylation using CH3CH2Cl and AlCl3. The plan is flawed because: A : When the alkyl halide interacts with AlCl3, the resulting carbocation can rearrange before it has a chance to react with the aromatic ring. B : Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation. C : The nitro group will direct the incoming alkyl group para position, rather than to the meta position. D : A blocking group is required to achieve this synthesis.
Answer:
Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.
Explanation:
The benzene ring in itself does not easily undergo electrophilic substitution reaction. Some groups activate or deactivate the benzene ring towards electrophilic substitution reactions.
-NO2 ia a highly deactivating substituent therefore, Friedel-Crafts alkylation of nitrobenzene does not take place under any conditions.
This reaction scheme is therefore flawed because Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.
number of molecules in lithium sulfate Li2So4
Do you think humans are responsible for global warming trends? Why or why not?
Answer:
Yes. At least some. There has been ups and downs in temperature ever since the Earth was created, and this is just another up in temperature. I do think that humans have made it worse though, with all of the greenhouse gases and things like that.
Hydrogen has an oxidation number of +1 in all compounds excepts when it binds with metals and has an oxidation state of -1.
Answer:
See explanation
Explanation:
In the periodic table, hydrogen is placed in group 1 for convenience. Hydrogen is not a metal, however, its common oxidation state is +1. It easily forms a univalent positive ion just like group 1 elements.
So, when hydrogen is combined with strongly electropositive metals such as sodium, lithium, etc, hydrogen accepts one electron and exhibits an oxidation state of -1 in those compounds.
Such compounds in which hydrogen is combined with strongly electropositive metals to give a binary compound is called a hydride.
Lithium and nitrogen react to produce lithium nitride:
6Li (s) + N2 (g) = 2Li3N (s)
How many moles of lithium nitride are produced when 0.400 mol lithium are used in this reaction?
a. 1.28 mol
b. 0.133 mol
c. 0.800 mol
d. 0.0667 mol
Answer:
B : 0.133 M
Explanation:
moles Li3N3 = 0.4 mol Li x (2 moles Li3N/6 moles Li) = 0.133 M
What is produced when concentrated aqueous sodium chloride is electrolysed?
1) How many molecules are in 0.02 moles of beryllium iodide?
Answer:
3 grams??
Explanation:
I think this would be the answer you are looking for.
The human body can get energy by metabolizing proteins, carbohydrates or fatty acids, depending on the circumstances. Roughly speaking, the energy it gets comes mostly from allowing all the carbon atoms in the food molecules to become oxidized to carbon dioxide CO2 by reaction with oxygen from the atmosphere. Hence the energy content of food is roughly proportional to the carbon content.
Let's consider alanine, C3H7NO2, one of the amino acids from which proteins are made, and glucose C6H12O6, one of the simplest carbohydrates. Using the idea above about energy content, calculate the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose.
Answer:
the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111
Explanation:
Given the data in the question;
To determine the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose, first we get the molar masses of both alanine and glucose
we know that;
Molar mass of alanine ( C₃H₇NO₂ ) = 89.09 g/mol
Molar mass of glucose ( C₆H₁₂O₆ ) = 180.16 g/mol
now, { metabolizing each gram }
moles of alanine = mass taken / molar mass
= 1g / 89.09 g/mol = 1/89.09 moles
moles of glucose = mass taken / molar mass
= 1g / 180.16 g/mol = 1/180.16 moles
In each molecule of alanine, we have 3 atoms of carbon.
Also, in each molecules of glucose, we have 6 atoms of carbon
so,
number of moles of Carbons in alanine = 3 × 1/89.09 moles = 0.03367
number of moles of Carbons in glucose = 6 × 1/180.16 moles = 0.0333
so ratio of energy will be the ratio of carbon atoms, which is;
⇒ 0.03367 / 0.0333 = 1.0111
Therefore, the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111
Calcium carbonate decomposes to form calcium oxide and carbon dioxide, like this:
CaCO3(s)→CaO(s)+CO2(g)
At a certain temperature, a chemist finds that a 9.0L reaction vessel containing a mixture of calcium carbonate, calcium oxide, and carbon dioxide at equilibrium has the following composition:
Compound Amount
CaCO3 25.3 g
CaO 14.9 g
CO2 33.7 g
Calculate the value of the equilibrium constant Kc for this reaction. Round your answer to 2 significant digits.
Answer: The value of the equilibrium constant Kc for this reaction is 0.088
Explanation:
[tex]Molarity=\frac{x}{M\times V_s}[/tex]
where,
x = given mass
M = molar mass
[tex]V_s[/tex] = volume of solution in L
Equilibrium concentration of [tex]CaCO_3[/tex] = [tex]\frac{25.3}{100\times 9.0}=0.028M[/tex]
Equilibrium concentration of [tex]CaO[/tex] = [tex]\frac{14.9}{56\times 9.0}=0.029M[/tex]
Equilibrium concentration of [tex]CO_2[/tex] = [tex]\frac{33.7}{44\times 9.0}=0.085M[/tex]
The given balanced equilibrium reaction is,
[tex]CaCO_3(s)\rightleftharpoons CaO(s)+CO_2(g)[/tex]
The expression for equilibrium constant for this reaction will be,
[tex]K_c=\frac{[CaO]\times [CO_2]}{[CaCO_3]}[/tex]
Now put all the given values in this expression, we get :
[tex]K_c=\frac{0.029\times 0.085}{0.028}=0.088[/tex]
hi, if your looking for extra points (50+) and br ainiest here is ur chance, answer this question correctly plz
Which of the following is a characteristic of both the Earth and the Moon?
Fossils and fossil
fuels under the
surface
Rocky surface
covered with
landforms
Flowing water in
Oceans and rivers
Atmosphere
containing oxygen
Answer:
rocky surface covered with landforms
Explanation:
When a hydrocarbon fuel is burned, almost all of the carbon in the fuel burns completely to form CO2 (carbon dioxide), which is the principal gas causing the greenhouse 102 ENERGY, ENERGY TRANSFER effect and thus global climate change. On average, 0.59 kg of CO2 is produced for each kWh of electricity generated from a power plant that burns natural gas. A typical new household refrigerator uses about 700 kWh of electricity per year. Determine the amount of CO2 production that is due to the refrigerators in a city with 300,000 households.
Answer:
1.239 * 10^8 Kg
Explanation:
Since all the electricity consumed comes from natural gas;
amount of electricity consumed = 700 * 300,000 = 2.1 * 10^8 kWh
So, amount of CO2 consumed is given by;
amount of electricity consumed * amount of CO2 per kWh
Hence,
Amount of CO2 = 2.1 * 10^8 kWh * 0.59 = 1.239 * 10^8 Kg
molar mass of Mg(CO3)
Answer:
[tex]\boxed {\boxed {\sf 84.313 \ g/mol}}[/tex]
Explanation:
The molar mass is the mass per mole of an element or substance. The values for atomic mass on the Periodic Table are used as the molar mass. Look up the molar masses for the elements in the formula.
Mg: 24.305 g/molC: 12.011 g/molO: 15.999 g/molAnalyze the formula. Magnesium and carbon have no subscript, so there is only one atom of each. Oxygen has a subscript of 3, so there are 3 atoms and the mass has to be multiplied by 3.
MgCO₃= 24.305 + 12.011+ 3(15.999) MgCO₃= 24.305+12.011+47.997=84.313 g/molThe molar mass of magnesium carbonate is 84.313 grams per mole.
The equation below illustrates the process of
Pb2+ (aq) + 11- (aq) → Pblu (s)
a) dissolution
b) precipitation
c) decomposition
Answer:
The correct answer is - b) precipitation.
Explanation:
In the given question the lead ion in an aqueous solution is mixed with the Leutium ion in an aqueous solution and forms an insoluble or solid salt. This type of reaction is referred to as precipitation reactions in chemistry.
Such reactions are helpful in determining if a particular ion is present in the solution or not.
Pb2+ (aq) + lu- (aq) → Pblu (s)
If you began a reaction with the following ions in solution, what would be the net ionic equation?
Na+, PO43–, Fe2+, and NO3–
Answer:
2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂
Explanation:
Let's consider the complete ionic equation between the ions present. It includes all the ions and the insoluble compounds (Fe₃(PO₄)₂ is insoluble).
Na⁺(aq) + 2 PO₄³⁻(aq) + 3 Fe²⁺(aq) + NO₃⁻(aq) ⇒ Fe₃(PO₄)₂ + Na⁺(aq) + NO₃⁻(aq)
The net ionic equation includes only the ions that participate in the reaction (not spectator ions) and the insoluble compounds.
2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂
CAN SOMEONE PLEASE HELP ME I WILL MARK AS BRAINLIEST :(
Answer:
ok so i did the problem and the answer was 8e+29
Explanation:
i dont really know what the answer is but thats the answer i got
sorry if this didnt help
Which of the following statements best describes the number of neutrons in an atom?
It is the same as the element's atomic number.
It is equal to the sum of atomic number and average atomic mass.
it is the same as the average atomic mass.
it is equal to the difference between atomic number and atomic mass number.
Answer:
its the last one
Explanation:
Which statement best describes the energy in the food web? A. The amount of energy available at level B depends on the amount of energy available at level C. B. The amount of energy available at level A depends on the energy provided from an abiotic source. C. The amount of energy available at level C is greater that the amount of energy available ate level A. D. The amount of energy available at level B is transferred to level A
Answer:
The amount of energy available at level A depend on energy provided from an a biotic source
pond water with microscopic organisms inside mixture or pure substance
Answer:
it's mixture
Explanation:
since pond is composed of not only microbes and also more aqatic animals so I think pond become mixture but not pure substance am I right or not...
Suppose an EPA chemist tests a 250.mL sample of groundwater known to be contaminated with nickel(II) chloride, which would react with silver nitrate solution like this: NiCl2(aq) + 2AgNO3(aq) → 2AgCl(s) + NiNO32(aq) The chemist adds 15.0mM silver nitrate solution to the sample until silver chloride stops forming. He then washes, dries, and weighs the precipitate. He finds he has collected 5.8mg of silver chloride. Calculate the concentration of nickel(II) chloride contaminant in the original groundwater sample. Round your answer to 2 significant digits.
Answer:
0.0010 w/v %
Explanation:
Based on the reaction:
NiCl₂(aq) + 2AgNO₃(aq) → 2AgCl(s) + Ni(NO₃)₂(aq)
Finding the moles of AgCl produced we can find the moles of NiCl in the reaction medium and its mass:
Moles AgCl -Molar mass: 143.32g/mol-:
5.8mg = 5.8x10⁻³g * (1mol / 143.32g) = 4.047x10⁻⁵ moles AgCl
Moles NiCl₂:
4.047x10⁻⁵ moles AgCl * (1mol NiCl₂ / 2mol AgCl) = 2.023x10⁻⁵ moles NiCl₂
Mass NiCl₂ -Molar mass: 129.60g/mol-:
2.023x10⁻⁵ moles NiCl₂ * (129.60g / mol) = 2.62x10⁻³g of NiCl₂ are produced.
And the concentration in w/v% is:
2.62x10⁻³g NiCl₂ / 250mL * 100 =
0.0010 w/v %thermal energy is what we call energy that come from ___ of matter
What is the molar mass of PbSO4?
Answer:
=303.2g
Explanation:
molar mass of Pb = 207.2g
atomic mass of S = 32g
atomic mass of O = 16g
Solution
PbSO4
= 207.2 + 32 + 4 (16)
= 239.2 + 64
= 303.2 g
The molar mass of compound lead sulfate is 207.2 g.
Molar mass of a compound or a molecule is defined as the mass of the elements which are present in it.The molar mass is considered to be a bulk quantity not a molecular quantity. It is often an average of the of the masses at many instances.
Molar masses of an element are given as relative atomic masses while that of compounds is the sum of relative atomic masses which are present in the compound.
atomic mass of S = 32g
atomic mass of O = 16g
PbSO₄= 207.2 + 32 + 4 (16)= 239.2 + 64 = 303.2 g.
Learn more about molar mass,here:
https://brainly.com/question/12127540
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At room temperature, oxygen is a gas and hydrogen is a gas. When they combine at room temperature, they form a _______________.
Answer: they can combine to form water or hydrogen peroxide.
Explanation:
sorry if it wrong i just looked it up lol. hope this helps tho
A certain protein transports a sodium ion from the inside of the cell membrane to the outside using active transport. Which of the following must be true? A. There is no change in concentration before or after transport. B. The transport process did not use chemical energy. C. After transport, the concentration of protein in the cell decreases. D. After transport, the concentration of sodium is lower inside the cell.