Answer:
What do you want answered?
Explanation:
HELP DUE IN 7 minutes TwT
Which product forms from the synthesis reaction between sodium (Na) and
sulfur (S)?
O A. Nasz
B. Nas
C. Na2S
O D. Na2S2
Answer:
Answer is C
Explanation:
the valency of sulphur is 2 ans sodium is 1
by crossing it forms NA2S
500mL of air are trapped in a tube over mercury at 25°C. It is found that, after six
days, the air has expanded so that 32mL have escaped the tube. What total
temperature change occurred over this period if the pressure remained constant?
Answer:
The new temperature is 19.072 K.
Explanation:
Charles's Law consists of the relationship that exists between the volume and the temperature of a certain quantity of ideal gas, which is maintained at a constant pressure. This law says that as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases because the temperature is directly related to the energy of the movement of the gas molecules.
In summary, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the quotient that exists between the volume and the temperature will always have the same value:
[tex]\frac{V}{T}=k[/tex]
Assuming that a certain volume of gas V1 that is at a temperature T1 at the beginning of the experiment varies up to a volume of gas V2, then the temperature will change to T2, and it will be true:
[tex]\frac{V1}{T1}=\frac{V2}{T2}[/tex]
In this case:
V1= 500 mLT1= 25 C= 298 KV2= 32 mLT2= ?Replacing:
[tex]\frac{500 mL}{298 K}=\frac{32 mL}{T2}[/tex]
Solving:
[tex]T2=32 mL*\frac{298 K}{500 mL}[/tex]
T2= 19.072 K
The new temperature is 19.072 K.
what is so unique about the ph scale 7?
Answer:
The pH scale 7 indicates neutral.
Explanation:
What is needed to change a phase of matter?
The addition or subtraction of thermal energy. For example if you heat up an ice cube, it will melt to become water. If you heat it even more, it will evaporate.
PLZ HELP PPPLLLLLZZZZ HELP ITS OVER DUE PPPPPPPPPPPLLLLLLLLLLLLLLLLLLLLZZZZZZZZZZZ
Please Help I need to finish this by the end of the day!
Answer:
C
Explanation:
If I am not mistaken, due to the conservation of mass, whatever mass is on the side of the reactants should be the same for the product side.
This means
218.76g+53.96g = 272.72g
272.72g-266.66g = 6.06g
So the answer should be C
5. Para la siguiente reacción: KClO3 (s) KCl(s) + O2
Si se descomponen 500 gramos de una muestra impura de clorato de potasio y se recogen 100 litros de O2 medidos bajo condiciones normales de presión y temperatura. Determine la pureza de la muestra.
Answer:
72.95%
Explanation:
Para resolver esta pregunta, debemos hallar las moles tóricas que se producirían en la reacción asumiendo que los 500g son únicamente de clorato de potasio haciendo uso de la reacción balanceada:
2KClO₃(s) → 2KCl(s) + 3O₂(g)
Donde dos moles de clorato de potasio producen tres moles de oxígeno.
Después de hallar las moles teóricas de oxígeno debemos hallar las moles producidas usando PV = nRT. La pureza SERÁ:
Moles producidas / moles Teóricas * 100
Moles clorato -Masa molar: 122.55g/mol-:
500g KClO₃ * (1mol / 122.55g) = 4.08 moles KClO₃
Moles O₂ teóricas:
4.08 moles KClO₃ * (3 moles O₂ / 2 moles KClO₃) = 6.12 moles
Moles producidas:
PV / RT = n
Donde P = 1atm a STP
V es volumen = 100L
R es constante de los gases = 0.082atmL/molK
T =273.15K a STP
Reemplazando:
1atm*100L / 0.082atmL/molK*273.15K = 4.46 moles
La pureza de la muestra es:
4.46 moles / 6.12 moles * 100 = 72.95%
The atomic number of calcium is 20. This number means that calcium has 20 protons. The atomic mass of calcium is 40. How many neutrons does calcium have? (Remember: protons + neutrons = atomic mass.)
ASAP NOW PLS
Answer:
Otherwise, positive charge means that the element lost an electron and negative charge means it gained an electron. (3) The atomic mass is equal to the sum of the number of protons and number of neutrons. An atom of the calcium-40 isotope has 20 neutrons in its nucleus.
how many molecules are in 45.0 g of water
which one is? Will give brainliest
Answer: 2Cr + 3Br2 Yields 3CrBr3
Explanation:
We know that 4a is not balanced because there are 3 Nitrogen atoms on the reactants side and 2 on the products side.
We know that 4c is not balanced because there are 4 Chlorine atoms on the reactants side and 2 on the products side. (Remember there are 2 Cl2 atoms. Therefore, 2 times 2 means there are 4 Chlorine atoms on the reactants side)
Finally, we know the answer is not 4d because there is 1 Potassium on the reactants side and 2 potassiums on the products side.
Therefore, the answer must be 4b, which contains 2 Chromium atoms and 6 bromine atoms on each side
1 point
have specific requirements that need to be met in order for an
entrepreneur to be considered.
O Loans
O Investments
O None of the other answers
O Grants
What does chemistry mean?
Answer:
The definition of chemistry is a branch of science that deals with the form and properties of matter and substances or the interaction between individuals.
How many grams of ammonia would be produced from the reaction of 2.64 moles of hydrogen gas reacting with excess nitrogen?
Answer:
29.92g
Explanation:
tell me if my answer is wrong
Why is it important to know characteristics that matter undergoes in chemistry? How can we analyze the relationships between chemical and physical changes and properties?
Answer:
It's important for scientists to know the properties of matter because all things are made up of matter. Each type of matter has different physical characteristics and scientists need to know and understand these characteristics to make calculations. ... The main phases of matter are solid, liquid, and gas.
Which of the following is equal to one molecule of calcium atoms?
6.022x10^23 molecules of Ca
6.022x10^23 atoms of Ca
6.022x10^20 molecules of Ca
6.022x10^22 atoms of Ca
Answer:
https://download.cnet.com/1-Click-Answers/3000-2378_4-10060189.html
Explanation:
Answer:
6.022x10^23 atoms of Ca
Explanation:
Find the pH of a 0.25 M solution of lactic acid, HC3H5O3 (Ka = 8.3 x 10 -4 ).
Answer:
pH → 1.83
Explanation:
Let's write the lactic acid as HLac, because it is a monoprotic weak acid.
HLac + H₂O ⇄ H₃O⁺ + Lac⁻ Ka
Initially we have 0.25 moles, so x amount has reacted. At the end, when the equilibrium is finished, we may have (0.25 - x) moles of acid, x moles of protons have been released and x moles of lactate were formed.
In order to find x, we use the acid constant, Ka. The expression for Ka is:
Ka = [H₃O⁺] . [Lac⁻] / [HLac]
8.3×10⁻⁴ = x² / (0.25-x)
8.3×10⁻⁴ (0.25 - x) = x²
8.3×10⁻⁴ . 0.25 - 8.3×10⁻⁴x - x² → this is a quadractic function
a = -1, b = 8.3×10⁻⁴, c = 2.07×10⁻⁴
We solve: (-b - √(b² - 4ac) / (2a)
(-8.3×10⁻⁴ - (√ ((8.3×10⁻⁴)² - 4 (-1) (2.07×10⁻⁴) ) / (2 . -1) = 0.0148
[H₃O⁺] = 0.0148 M
- log [H₃O⁺] = pH → - log 0.0148 = 1.83
The pH is defined as the power of Hydrogen. The pH of a 0.25 M solution of lactic acid is 1.83.
[tex]\bold { CH_3COOH \rightarrow CH_3 COO + H^+\ \ \ \ \ \ \ \ \ \ \ \ (Ka = 8.3 x 10 -4 ).}[/tex]
Initial concentration of lactic acid is 0.25 M, So, [tex]x[/tex]. At the end of equilibrium [tex]x[/tex] amount of lactic acid dissociates.
So, concentration of the Hydrogen ion in the (0.25 - [tex]x[/tex])
[tex]x[/tex] can be found out by using the dissociation constant formula,
[tex]\bold {Ka = \dfrac {[H^+][CH_3COO^-]}{[Ch_3COOH]}}\\[/tex]
[tex]\bold {8.3x10^-^4= \dfrac {[x][x]}{[2.5- x]}}\\\\\bold {8.3x10^-^4= \dfrac {[x^2]}{[2.5- x]}}\\\\\bold {x^2= 8.3x10^-^4\times [2.5- x]}}\\\\\bold {8.3x10^-^4 \times 0.25 - 8.3x10^-^4 x - x^2 = 0}[/tex]
The equation above is a quadratic equation, solving it we get,
The concentration of protons = 0.0148 M
Put this into the pH formula,
[tex]\bold {pH = -log [H^+]}[/tex]
[tex]\bold {pH = -log [ 0.0148]}\\\\\bold {pH = 1.83}[/tex]
Therefore, the pH of a 0.25 M solution of lactic acid is 1.83.
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Which statement about Bohr’s model of the atom is false?
A. Electrons cannot be between energy levels.
B. Electrons orbit the nucleus.
C. An electron’s path is not known exactly.
D. Electrons exist in energy levels.
The statement which is false about Bohr's model is option C, "an electron's path is not known exactly". Electron's path can be determined using the knowledge of different energy levels.
What are energy levels?Energy levels in an atom is circular paths having fixed energy through which the electrons are revolving around the nucleus. This model of atom was proposed by Niels Bohr.
According to Bohr's atomic model, electrons are revolving through fixed energy levels around the nucleus, where the velocity and momentum of electron and the radius of the atom can be determined using the model.
Bohr's model of atom contributed well to the atomic structure and helped to determine the energy of electronic transitions.
Hence, the statement an electron's path is not known is false.
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When collecting temperature as a function of time for the reaction of KOH with HCL, which time is most significant
Answer:
At the completion of reaction.
Explanation:
The time when the reaction take places is the most significant time for measuring temperature of the solution because on this time the temperature will decrease or increase. Some reactions releases heat energy upon completion we called them exothermic reactions whereas some absorb heat energy from the surrounding, decreases the temperature which is known as endothermic reaction so measuring temperature at the completion of reaction is the correct time.
Molar mass of Ag2SO4
Full work Pls
How many grams of Ag2S
are produced from 10.0
grams of AgI?
10
AgI + Nazs
Ag2S +NaI
Answer:
10.0 g of AgI will produce 5.28 g of Ag₂S
Explanation:
The balanced equation of the reaction is given below:
2AgI + Na₂S ----> Ag₂S + 2NaI
From the equation of reaction, 2 moles of AgI produces 1 mole of Ag₂S
The moles of a substance is related to its mass by a quantity known as molar mass which is defined as the mass of one mole of that substance.
Molar mass of AgI = (108 + 127) g = 235 g
Molar mass of Ag₂S = (108 × 2 + 32) g= 248 g
Mass of 2 moles of AgI = 2 × 235 g = 470 g
470 g of AgI produces 248 g of Ag₂S
10 g of AgI will produce 248 /470 × 10 g of Ag₂S = 5.28 g
Therefore, mass of Ag₂S produced = 5.28 g
do i have to know the chemical and physical properties of alloys? only chemistry students answer this.
Answer:
yes you do so you know how strong it is how maluble it's is so it can be customised to it's specific use
Answer:
alloy's properties are usually different from those of its component elements. Alloy constituents are usually measured by mass. Unlike pure metals, most alloys do not have a single melting point; rather, they have a melting range in which the substance is a mixture of solid and liquid.
physical properties of alloys:-Alloy steels have a wide range of special properties, such as hardness, toughness, corrosion resistance, magnetizability, and ductility. Nonferrous alloys, mainly copper–nickel, bronze, and aluminum alloys, are much used in coinage.
chemical properties of alloys:-Pure metals are useful but their applications are often limited to each individual metal's properties. Alloys allow metal mixtures that have increased resistance to oxidation, increased strength, conductivity, and melting point; Essentially any property can be manipulated by adjusting alloy concentrations.
dnt learn all thr properties.
these are the main properties..u can learn thse only. hope it will help u
help i dont wanna read
Answer:
I do not really no sorry
Explanation:
:))
someone pls help me!
Answer:
I think its A-When the car is cruising straight down a highway
How many grams of oxygen are required to burn 13.5 g of acetylene
Answer:
41.54 grams of oxygen are required to burn 13.5 g of acetylene
Explanation:
The balanced reaction is:
2 C₂H₂ + 5 O₂ → 4 CO₂ + 2 H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
C₂H₂: 2 moles O₂: 5 moles CO₂: 4 moles H₂O: 2 molesBeing the molar mass of the compounds:
C₂H₂: 26 g/moleO₂: 32 g/moleCO₂: 44 g/moleH₂O: 18 g/moleBy reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
C₂H₂: 2 moles* 26 g/mole= 52 gramsO₂: 5 moles* 32 g/mole= 160 gramsCO₂: 4 moles* 44 g/mole= 176 gramsH₂O: 2 moles* 18 g/mole= 36 gramsYou can apply the following rule of three: if by stoichiometry 52 grams of acetylene react with 160 grams of oxygen, 13.5 grams of acetylene react with how much mass of oxygen?
[tex]mass of oxygen=\frac{13.5 grams of acetylene*160 grams of oxygen}{52 grams of acetylene}[/tex]
mass of oxygen= 41.54 grams
41.54 grams of oxygen are required to burn 13.5 g of acetylene
Where do animals obtain their chemical energy? I WILL MARK BRAINLEST HELP ASAP!!!
from plants only
from plants and animals
from animals only
directly from solar energy
Answer:
from plants and animals.
For the balanced equation shown below, how many moles of N2 reacted, if 155 moles of NH3 are produced?
3H2 + N2 => 2NH3
Answer: 1 mole nitrogen produces 2 moles ammonia
How many moles you need for 155 mol ammonia?
155/2 moles
Explanation:
Did anyone do this worksheet (science)
Transcribe the following piece of DNA ........AAG-CCA-TGA-ACA
Answer:
TTC-GGT-ACT-TGT I could be wrong because A could eather be considered a U or a T, but u could also use UUC-GGU-ACU-UGU
Help!!! Would give brainliest
Answer: Acids have a pH of less than 7 and generally form [tex]H^+[/tex] when dissolved in solution. [tex]H_2SO_4[/tex] is an example of acid.
Bases have a pH of more than 7 and generally form [tex]OH^-[/tex] when dissolved in solution. [tex]Ca(OH)_2[/tex] is an example of base.
Water is neutral and has a pH of exactly 7. Therefore in chemical equations it can act as acid or a base.
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution. pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
pH values range from 1 to 14. Acids have a pH range from 1 to 6.9, water is neutral with pH of 7 and bases have pH ranging from 7.1 to 14.
Acids form hydrogen ions when dissolved in water and bases form hydroxide ions when dissolved in water. Water [tex]H_2O)[/tex] is amphoteric and thus can behave as an acid or a base.
[tex]H_2SO_4\rightarrow 2H^++SO_4^{2-}[/tex]
[tex]Ca(OH)_2\rightarrow Ca^{2+}+2OH^[/tex]
What is the standard cell notation of a galvanic cell made with aluminum and
nickel?
A. Ni(s) | Ni2+ || A13+(aq) | Al(s)
B. Al(s)| A13+(aq) || Ni2+(aq) | Ni(s)
C. Ni2+(aq) | Ni(s) || Al(s) | A13+(aq)
D. A13+(aq) | Al(s) || Ni(s) | Ni2+(aq)
D. A13+(aq) | Al(s) || Ni(s) | Ni2+(aq). The standard cell notation of a galvanic cell made with aluminum and nickel is A13+(aq) | Al(s) || Ni(s) | Ni2+(aq).
How do you represent galvanic cells in cell notation?The anode is on the left, and the cathode is on the right. The convention specifies that metals come first and then the metal ions present in the electrolyte represent the cell. And a vertical line is required to separate these two.
What does common cell notation entail?Voltaic or galvanic (spontaneous) cells are denoted by cell notations in shorthand. This special shorthand describes the anode, cathode, and electrode components as well as the reaction circumstances (pressure, temperature, concentration, etc.).
What materials make up a galvanic cell?A galvanic cell is made up of two distinct metals (electrodes), connected externally to complete a circuit and through a conducting liquid (an electrolyte).
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