Answer:
poluição atmosférica
Explanation:
O que eles estão tentando falar na pergunta é que a que termo nos referimos como a introdução de partículas estranhas na forma de suspensão etc. na atmosfera.
Este termo é conhecido como poluição do ar. É chamado assim porque, adulteramos a constituição original do ar, introduzindo esses novos componentes.
Esses componentes introduzidos muitas vezes têm um efeito adverso na composição da qualidade do ar.
I NEED HELP ASAP !!!!!!!!!!!!!!
IF YOUR RIGHT ILL LIKE YOUR TIK TOKS OR GIVE U MOST BRAINLY
What is involved in redox reactions
A.the transfer of electrons between reactants
B.the bonding of ions to form chemical compounds
C.the addition of water to break down food macromolecules
D.the breaking down of water into hydrogen and oxygen atoms
Answer:
A
Explanation:
Redox reactions are comprised of two parts, a reduced half and an oxidized half, that always occur together. The reduced half gains electrons and the oxidation number decreases, while the oxidized half loses electrons and the oxidation number increases.
Answer:
a
Explanation:
What is the Ka of a 0.0796 M solution of nitrous acid (HNO2) with a pH of 2.95?
Answer:
Coefficient = 1.58
Exponent = - 5
Explanation:
pH = 2.95
Molar concentration = 0.0796M
Ka = [H+]^2 / [HA]
Ka = [H+]^2 / 0.0796
Therefore ;
[H+] = 10^-2.95
[H+] = 0.0011220 = 1.122 × 10^-3
Ka = [H+] / molar concentration
Ka = [1.122 × 10^-3]^2 / 0.0796
Ka = (1.258884 × 10^-6) / 0.0796
Ka = 15.815 × 10^-6
Ka = 1.58 × 10^-5
Coefficient = 1.58
Exponent = - 5
what is the concentration of nitric acid solution with pH 2
Answer:
Nitric acid = HNO3
HNO3 → H+ NO3 2-
Since it's an acid
pH = -log of concentration of H+ ions
pH = -log (H+)
2 = -log(H+)
Taking antilog of both sides
H+ = 10^-2
= 0.01
Concentration of nitric acid = 0.01mol/dm^-3
Hope this helps.
Calculate the grams of calcium present in 70 grams of calcium chloride.
Answer:
37.1g of Ca
Explanation:
Hello,
Molecular formula for calcium chloride = CaCl
Molar mass = 40 + 35.5 = 75.5g/mol
Assuming there's one mole of CaCl
1 mole = mass / molar mass
Mass = 1 × 75.5
Mass = 75.5g
75.5g of CaCl contains 40g of Calcium
70g of CaCl will contain x g of Calcium
X = (70 × 40) / 75.5
X = 37.086g
Therefore, 70g of CaCl contains approximately 37.1g of Ca
Determine the genotypes of offspring 1-8.
A very good example of soft water is A. Distilled water B. Sea water C. Underground water D. Polluted water
Answer:
The answer is option A.
Distilled water
Since all the chemicals that will cause hardness in the water has been removed.
Hope this helps.
Esterification is what type of reaction? 1.addition 2.neutralization 3.combustion 4.equilibrium
Answer:
Equilibrium reaction
Explanation:
Name the first 20 elements of the pereodic table
Answer:
alkali metals hydrogen lithium sodium potassium rubidium cesium francium alkaline earth metals beryllium magnesium calcium strontium barium radium group 3 boron aluminium gallium indium thalium carbon family carbon silicon germanium tin lead
Explanation:
i hope this will help you :)
There's Hydrogen and Helium
Then Lithium, Beryllium
Boron, Carbon everywhere
Nitrogen all through the air
With Oxygen so you can breathe
And Fluorine for your pretty teeth
Neon to light up the signs
Sodium for salty times
Silicon
(Phosphorus, then Sulfur) Chlorine and Argon
(Potassium) And Calcium so you'll grow strong
(Scandium) Titanium, Vanadium and Chromium and Manganese
This is the Periodic Table
Noble gas is stable
Halogens and Alkali react aggressively
Each period will see new outer shells
While electrons are added moving to the right
Iron is the 26th
Then Cobalt, Nickel coins you get
Copper, Zinc and Gallium
Germanium and Arsenic
Selenium and Bromine film
PLEASE HELP
Which Is a result of topsoil loss A increase soil fertility B poor crop production C soften soil surface D deposition of aggregate
Answer:
B - Poor crop production
Explanation:
I just did the quiz on Edge 2021
Answer:
b
Explanation:
Give examples of partially miscible liquids.
Answer: Water, alcohols, aldehydes, and ketones.
Explanation:
Answer:
Examples of Partially Miscible and Immiscible Liquids: Illustrations of immiscible liquids are cooking oil and water, milk and oil, gasoline and water, and liquid metals and water. There are as well partially miscible liquids such as honey and water, butanol and water, and potassium chloride and water.
Explanation:
Hope it helps
Which refers to a measure of how acidic or basic a solution is? pH solubility reactiveness hardness
Answer:
it is Ph of solution that tells you the acdic and basic nature of solution
if PH is lower than 7 the soution is acidic and if PH is larger than 7 the solution is basic
Explanation:
Answer:
A. Ph
Explanation:
Which one of the following oxide has both acidic and basic properties?
A. MgO
B. N2O
C. Al2O3
D. SO2
Answer:
The answer is C
Explanation:
Aluminium oxide is an amphoteric oxide.
MgO is a basic oxide.
N2O is an acidic oxide.
SO2 is an acidic oxide.
I need an answer,
Chemistry "question":
Name this molecule.
Answer:
3–methylhexane.
Explanation:
To effectively name the compound given in the question, do the following:
1. Locate the longest continuous carbon chain. This gives the parent name of the compound.
2. Identify the substituent attached to the compound.
3. Locate the position of substituent in the compound using the lowest possible count.
4. Combine the above to get the name of the compound.
Now, let us name the compound with the illustration given above.
1. The longest continuous carbon chain is carbon 6 i.e Hexane
2. The substituent attached to compound is methyl i.e CH3.
3. The substituent i.e CH3 is located at carbon 3.
4. We shall combine the above to get the name of the compound. Therefore, the name of the compound is:
3–methylhexane.
what type of electromagnetic waves does the human eye see as the colors red, blue, or green
Answer:
Visible light waves
Explanation:
Visible light waves are the only electromagnetic waves we can see. We see these waves as the colors of the rainbow. Each color has a different wavelength. Red has the longest wavelength and violet has the shortest wavelength.
write the steps you would use for making tea.use the words solution,solvent,solute,dissolve,soluble,insoluble,filtrate and residue
Which compound contains covalent bonds? AlN Ca3N2 NaCl HCl
Answer:
Ca3N2
Explanation:
Which symbol can be used to indicate the pressure at which a chemical reaction is carried out?
25°C
2 atm
Pt
Answer:
2 atm
Explanation:
Different symbols have different meanings in chemistry. For example, the symbol Δ = adding energy to the reactants.
To identify whether the reactants combine with a specific pressure, we have to use the symbol atm, in such a case 2 atm.
Hope that helps!
Why does sugar mix more in hot water than in cold water?
Answer:
this is because hot water has more energy than cold water
From where in the solar system did scientists conduct their spectral analyses in
1948? How do you know?
Answer:
Both Earth and Space
Explanation:
Because in 1948 there was no ability to analyze from space but in 1966 there was.
Which of the following has the shortest bond lenght Options A). H2 B).N2 C).O2 D).F2
Answer:
B. N2
Explanation:
The triple bonds pull the atoms closer together, and since N2 is the only molecule with the triple bond, it is the shortest bond length.
During which event does the moon appear closer? Select one: a. Apogee b. Penumbra c. Perigee d. Umbra
Answer:
Perigee
Explanation:
In Perigee, The moon appears closer.
What is the complete ionic equation for the reaction between Na 2 SO 4 and CaCl 2 ?
Answer:
Na2SO4 + CaCl2 → 2Na+ SO4 2- + Ca2+ 2Cl-
Hope this helps.
Answer:
2Na+(aq)+SO42-(aq)+Ca2+(aq)+2Cl-(aq)->CaSO4(s)+2Na+(aq)+2Cl-(aq)
Explanation:
help on this one, i have no idea how to do it
Answer:
c
Explanation:
Which statement is true of a reversible reaction at equilibrium?
А.
The concentration of reactants is less than the concentration of products.
B.
The concentration of reactants and the concentration of products are equal.
с.
The concentration of reactants is greater than the concentration of products.
D.
The concentration of reactants and the concentration of products are constant.
Ε.
The concentration of reactants is decreasing and the concentration of products is increasing,
Answer:
D.
The concentration of reactants and the concentration of products are constant.
Explanation:
pls mark as brainliest
Consider the intermediate chemical reactions. 2 equations. First: upper C a (s) plus upper C upper O subscript 2 (g) plus one half upper O subscript 2 (g) right arrow upper C a upper C upper O subscript 3 (s). Delta H 1 equals negative 812.8 kilojoules. Second: 2 upper C a (s) plus upper O subscript 2 (g) right arrow 2 upper C a upper O (s). Delta H 2 equals negative 1, 269 kilojoules. The final overall chemical equation is Upper Ca upper O (s) plus upper C upper O subscript 2 (g) right arrow upper C a upper C upper O subscript 3 (s).. When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed. is halved. has its sign changed. is unchanged.
Answer: When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.
Explanation:
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The overall chemical reaction follows:
[tex]CaO(s)+CO_2\rightarrow CaCO_3(s)[/tex] [tex]\Delta H^o_{rxn}=?[/tex]
The intermediate balanced chemical reaction are:
(1) [tex]Ca(s)+CO_2(g)+\frac{1}{2}O_2(g)\rightarrow CaCO_3(s)[/tex] [tex]\Delta H_1=-812.8kJ[/tex]
(2) [tex]2Ca(s)+O_2(g)\rightarrow 2CaO(s)[/tex] [tex]\Delta H_2=-1269kJ[/tex]
The expression for enthalpy of the reaction follows:
[tex]\Delta H^o_{rxn}=[1\times (\Delta H_1)]+[\frac{1}{2}\times (-\Delta H_2)][/tex]
Hence, when the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.
Answer:
A. is halved and has its sign changed.
Explanation:
just took the test on edge
The reaction of nitrogen gas and oxygen gas to form nitrogen monoxide gas is shown below. If the measured concentrations of all three chemicals at some point in time are: [N2] = 0.80 M
[O2] = 0.050 M
[NO] = 0.10 M
Which statement is TRUE about the reaction at this point in time? N2(g) + O2(g) ⇄ 2 NO(g) K = 0.10
The reaction is at equilibrium.
The reverse reaction is occurring at a faster rate than the forward reaction.
The forward reaction is occurring at a faster rate than the reverse reaction.
This set of concentration values is impossible because the concentrations of N2 and O2 must be the same.
Answer:
The reverse reaction is occurring at a faster rate than the forward reaction.
Explanation:
When the reaction:
aA + bB ⇔ cC + dD
has not reached the balance, it is possible to calculate:
[tex]Qc=\frac{[C]^{c}*[D]^{d} }{[A]^{a}*[B]^{b} }[/tex]
where Q is called the reaction quotient, and the concentrations expressed in it are not the equilibrium concentrations, but other concentrations given at a time of the reaction.
Comparing Qc with Kc allows to find out the status and evolution of the system:
If the reaction quotient is equal to the equilibrium constant, Qc = Kc, the system has reached chemical equilibrium. If the reaction quotient is greater than the equilibrium constant, Qc> Kc, the system is not in equilibrium. In this case the direct reaction predominates and there will be more product present than what is obtained at equilibrium. Therefore, this product is used to promote the reverse reaction and reach equilibrium. The system will then evolve to the left to increase the reagent concentration. If the reaction quotient is less than the equilibrium constant, Qc <Kc, the system is not in equilibrium. The concentration of the reagents is higher than it would be at equilibrium, so the direct reaction predominates. Thus, the system will evolve to the right to increase the concentration of products.In the case of the reaction:
N₂ (g) + O₂ (g) ⇄ 2 NO (g)
[tex]Qc=\frac{[NO]^{2} }{[N_{2} ]*[O_{2} ] }[/tex]
Being:
[N₂] = 0.80 M [O₂] = 0.050 M [NO] = 0.10 Mand replacing:
[tex]Qc=\frac{0.10^{2} }{0.80*0.050 }[/tex]
you get:
Qc= 0.25
Being Kc=0.10, Qc>Kc. Then the system is not in equilibrium and will evolve to the left to increase the concentration of reagents. So, the reverse reaction is occurring at a faster rate than the forward reaction.
When determining the mass of product used or reactant consumed, the number of moles must be determined before comparing two substances because a) moles react. b) atoms have the same mass but moles are different for each substance. c) different substances have different masses due to their atomic make-up. d) masses are the same for different substances.
Answer:
moles react.
Explanation:
In a chemical reaction equation, we know that chemical species react in moles. It is actually the moles of the individual chemical species that participate in a chemical reaction and not the masses of those species.
In solving stoichiometric problems, it is mandatory to use moles as a conversion factor in calculating the mass of product formed or the mass of reactant consumed. We often read off the number of moles that reacted from the balanced reaction equation and then convert the reacting mass of species given to the number of moles of that specie that actually participated in the reaction in order to obtain any required information from a reaction.
Answer:
it is NOT moles react. Just got it wrong on test
Explanation:
synthetic fibres catch fire easily so they are_____
Answer:
artificial polymer fibers that melt upon heating
Explanation:
what is the other metal react iron which get rusted
Answer:
The answer is OXIDATION REACTION.
Answer:
There's no other metal.
Explanation:
Iron reacts only with water and air to get the object rusted. There is no other metal which reacts with iron to get the object rusted.
However,
Zinc can be used to protect Metal from Rusting.
Which describes gneiss?
igneous
formed from shells
tends to split along bands
grains randomly arranged
Answer:
tends to split along bands
Explanation:
Answer: C
Explanation: E2022