What is the mass percentage of copper in a 250 g sample of brass. Brass is made of copper and zinc and copper content of the sample is 150 g
Answer:
Percentage of copper in sample = 60%
Explanation:
Given:
Mass of copper = 150 gram
Mass of brass = 250 gram
Find:
Percentage of copper in sample
Computation:
Percentage of copper in sample = [Mass of copper / Mass of brass]100
Percentage of copper in sample = [150/250]100
Percentage of copper in sample = [0.6]100
Percentage of copper in sample = 60%
Please somone help me with a chemistry question brainliest to whoever answers correctly and 20 points
Answer:
342.15 g/mol
..........
Can someone help me
Answer:the second largest one
Explanation:
both weels are pushing at it
how many moles are in 20 grams of argon
Answer:
There are 0.5 mole in 20g of argon.
Explanation:
40 g of argon = 1mole
Then 20g of argon is,
→ 1/40 × 20
→ 0.5 mole
Answer:
[tex]n = \frac{mass}{molar \: mass} \\ n = \frac{20g}{39.948 \frac{g}{mol} } \\ n = 0.5 \: mol \: of \: argon[/tex]
Explanation:
hope this makes sense
:)
How much heat must be transferred to 3500 g of liquid water to change the
water's temperature from 27°C to 32°C? (The specific heat capacity of liquid
water is 4.186 J/g.°C.)
O A. 170 J
O B. 73,000 J
O C. 470,000
O D. 2900 J
Identify the total number of moles involved in the reaction
2C4H10(g) + 13 O2(g) – 10 H2O(g) + 8 CO2(g)
Answer:
33 moles
Explanation:
The given chemical reaction is 2C₄H₁₀(g) + 13 O₂(g) → 10H₂O(g) + 8CO₂(g)
The number of moles of each reactant are as follows;
Butane, C₄H₁₀ = 2 moles of (g) + 13 (g) → 10H₂O(g) + 8CO₂(g)
Oxygen gas, O₂ = 13 moles
Water, H₂O = 10 moles
Carbon dioxide, CO₂ = 8 moles
The total number of moles, n = (2 + 13 + 10 + 8) = 33
∴ The total number of moles involved in the reaction, n = 33 moles.
The chemical bonding in sodium phosphate, Na3PO4 is classified as
A) ionic, only
B) metallic, only
C) both covalent and ionic
D) covalent, only
Answer:
C
Explanation:
The phosphate group PO4 is bonded covalently (bond between two non metals). While the sodium being bonded to the phosphorus atom is an ionic bond (bond between a metal and a non metal)
The chemical bonding in sodium phosphate, Na3PO4 is classified as both covalent and ionic. Therefore, option C is correct.
What is chemical bonding ?An enduring attraction between atoms or ions known as a chemical bond is what allows molecules and crystals to form. The bond may be created by the sharing of electrons in covalent bonds or by the electrostatic attraction of two oppositely charged ions, as in ionic bonds.
Chemical bonds are formed when the atoms in a compound's molecule are brought together and kept together by a powerful combining force. Ionic and covalent bonds are the two different types of chemical bonds.
Molecules are held together by chemical bonds, which also make transient connections necessary for life. chemical bonds, including as ionic, covalent, and hydrogen bonds, as well as London dispersion forces.
Thus, option C is correct.
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A compound being used in experimental medicine is 78.14% boron (B) and 21.86% hydrogen (H). The empirical formula of the compound will have a boron to hydrogen ratio of
Explanation:
I did it step by step so It would be easier to understand:)
Se realiza una mezcla de minerales de Cu y Fe: 20 kg FeS2 (pirita), 70 kg de Fe2O3 (hemetita) 15 kg de CuFe2 (calcopirita) y 90 kg de CuO (tenorita). Calcule: Porcentaje de hierro Porcentaje de cu Porcentaje de azufre y oxigeno
Answer:
34.78% Fe
39.66% Cu
5.48% S
20.07% O
Explanation:
Para resolver esta pregunta debemos hallar la masa de cada átomo en cada mineral. Así, podremos hallar el porcentaje de cada átomo:
Pirita (Fe: 55.845g/mol; S: 32.065g/mol; FeS2: 119.975g/mol)
Masa Fe:
20kg FeS2 * (1*55.845g/mol / 119.975g/mol) = 9.31kg Fe
Masa S:
20kg FeS2 * (2*32.065g/mol / 119.975g/mol) = 10.69kg S
Hemetita (Fe: 55.845g/mol; O: 16g/mol; Fe2O3: 159.688g/mol)
Masa Fe:
70kg Fe2O3 * (2*55.845g/mol / 159.688g/mol) = 48.96kg Fe
Masa O:
70kg Fe2O3 * (3*16g/mol / 159.688g/mol) = 21.04kg O
Calcopirita (Fe: 55.845g/mol; Cu: 63.546g/mol; CuFe2: 175.236 g/mol)
Masa Fe:
15kg CuFe2 * (2*55.845g/mol / 175.236 g/mol) = 9.56kg Fe
Masa Cu:
15kg CuFe2 * (1*63.546g/mol / 175.236 g/mol) = 5.44kg Cu
Tenorita (O: 16g/mol; Cu: 63.546g/mol; CuO: 79.545 g/mol)
Masa O:
90kg CuO * (1*16g/mol / 79.545 g/mol) = 18.10kg O
Masa Cu:
90kg CuO * (1*63.546g/mol / 79.545 g/mol) = 71.90kg Cu
Masa Total: 20kg + 70kg + 15kg + 90kg = 195kg
Porcentaje Hierro:
9.31kg Fe + 48.96kg Fe + 9.56kg Fe / 195kg * 100 =
34.78% Fe
Porcentaje Cobre:
5.44kg Cu + 71.90kg Cu / 195kg * 100 =
39.66% Cu
Porcentaje Azufre:
10.69kg S / 195kg * 100 =
5.48% S
Porcentaje Oxígeno:
21.04kg O + 18.10kg O/ 195kg * 100 =
20.07% O
Is proton number always equal to electron number ?
Explanation:
this is ur answer i hope.........
Describe the chemical reaction based on the chemical equation below. Also, explain whether the equation is balanced. NH3(g)+o2=NO(g)+H2O(I)
Answer:
2 moles of ammonia gas (NH₃) reacts with 5/2 moles of oxygen gas (O₂) to produce 2 moles of nitrogen monoxide gas (NO) and 3 moles of liquid water (H₂O)
Explanation:
The chemical equation is:
NH₃(g) + O₂(g)⇒ NO(g) + H₂O(I)
First, we have to distinguish which are reactants and which are products.
Reactants ⇒ left side: NH₃ (ammonia gas) and O₂ (oxygen gas)
Products ⇒ right side: NO (nitrogen monoxide) and H₂O (water)
Thus, ammonia gas reacts with oxygen gas to produce nitrogen monoxide gas and liquid water.
The reaction is not balanced, because it does not has the same number of atoms of each chemical element in both sides. To balance, we have to write a coefficient of 3 for H₂O, then a coefficient of 2 for NH₃ (to balance H atoms), then a coefficient of 2 for NO, and finally a coefficient of 5/2 for O₂ (to obtain 5 atoms of O in both sides):
2 NH₃(g) + 5/2 O₂(g)⇒ 2 NO(g) + 3 H₂O(I)
According to the balanced equation, 2 moles of ammonia gas (NH₃) reacts with 5/2 moles of oxygen gas (O₂) to produce 2 moles of nitrogen monoxide gas (NO) and 3 moles of liquid water (H₂O).
How many moles of aluminum are in this aluminum can? Answer: ____________ (25 pts) Calculate the number of aluminum atoms in this can. Answer: _______________ (25 pts) The Amount of Aluminum is 12.69g
Answer:a)No of moles of Aluminium=0.4703
b)number of aluminum atoms=2.832 x 10^23 atoms
Explanation:
a)Given that The Amount/ Mass of Aluminum is 12.69g
We know that
No of moles =Mass/ Molar mass
Molar mass of Aluminium, Al is 26.982 g/mol
No of moles =12.69g/26.982 g/mol
No of moles =0.4703
Also
b) 1 mole of aluminium must contain 6.022 x 10^23 atoms of aluminium
which is known as Avogadro's constant.
Therefore, 0.4703 moles will contain 0.4703 x 6.022 x 10^23 atoms =2.832 x 10^23 atoms
La formula quimica de la molecula de agua H20 , si H = 1 gramos y O = 16 gramos . Cual es su composicion porcentual ? 88,88 % de O y 11,11 % de H 88,88 % de H Y 11,11% de O 80 % de O Y 20 % de H 90% de O Y 10 % de H
Answer:
88,88 % de O y 11,11 % de H
Explanation:
La composición porcentual se define como la masa que hay de cada mol de átomo en 100g. Las moles de agua en 100g son:
Masa molar agua:
2H = 2*1g/mol = 2g/mol
1O = 1*16g/mol = 16g/mol
Masa molar = 2 + 16 = 18g/mol
100g H2O * (1mol / 18g) = 5.556 moles H2O.
Moles de hidrógeno:
5.556 moles H2O * (2mol H / 1mol H2O) = 11.11 moles H
Moles Oxígeno = Moles H2O = 5.556 moles
La masa de hidrógeno es:
11.11mol * (1g/mol) 11.11g H
La masa de oxígeno es:
5.556 mol * (16g / 1mol) = 88.89g O
Así, el porcentaje de O es 88.89% y el de H es 11.11%. La opción correcta es:
88,88 % de O y 11,11 % de HYou are given a sample of an element with ONE valence electron.
EXPLAIN how and where to find this element in the periodic table
Answer:
the amount of valence electron, cna be found in the periodic table, which is called the atomic number which is top of the symbol
hope this helps!!! best fo luck to you
What factors generally determine whether a reaction happens or not?
A. Reaction rate and color
B. Presence of water and salt
C. Enthalpy and entropy
D. Keg and Ka
Answer:
Explanation:
The answer is C Enthaply and entropy because temperature plays a big role in reactions
Answer:
c
Explanation:
a p e x :)
How many grams of calcium chloride would you measure if you needed to
add 0.125 moles of calcium chloride to 100mL of water?
Answer: cuhh
Explanation:
Which property of metals makes them good conductors of electricity?
A. Their melting point
B. Their mobile electrons
C. Their hardness
D. Their ductility
Answer:
their mobile electrons
Once upon a time, a mother duckling sat on her eggs with great impatience. How long would it be before they hatched? Finally, one summer day, the mother duckling watched as the eggs cracked, and her cute, yellow ducklings waddled into the world. She was filled with joy until she noticed that one egg, which was larger than all of the others, remained. After many hours, the egg cracked. A large, gray duckling emerged. The mother duck was horrified at the duckling's appearance. The mother duck's only comfort was that the ugly duckling could swim and dive under the water.
As the ugly duckling grew, many animals in the pond criticized him. His feathers were too dark, his neck was too long, and his body was too big. His fellow ducklings refused to recognize that underneath the feathers, the ugly duckling was kind, good, and gentle. The ugly duckling shed many tears because none of the other animals would play with him.
Read this excerpt from the fairy tale The Princess and the Pea.
One evening, there was a terrible storm. The wind howled, thunder shook the stone walls, and lightning filled the dark night sky. Through the pelting of the rain, there came a knock at the door. When the king opened the door, he saw a bedraggled girl, soaked to the skin and covered in mud. He ushered her into the castle so that she could warm herself by the fire.
"Why is a young servant girl like you wandering about on such a ferocious night?" queried the king.
The disheveled maiden looked at the king in disbelief. "I am a princess, come to see the prince," she explained, all the while shivering.
The king summoned his wife, the queen, for advice. The queen looked at the hideous creature in disbelief, thinking that no princess would ever allow herself to be found in such a state.
How do the authors illustrate the theme that people should not be judged based on their appearances?
Both authors show that the main characters are not afraid of getting wet and dirty in order to live active lives.
Both authors show the main characters being labeled in a negative manner based on their appearances.
Both authors showed the main characters exercising patience with other people.
Both authors showed the main characters wanting to make friends with others.
Answer:
Im not 100% sure this is correct but i think the answer would be
Both authors show the main characters being labeled in a negative manner based on their appearances.
Explanation:
because
both the ugly ducking and the princess are not in the best conditions so i think that would be why that is the answer choice
Answer: i think it's Both authors show the main characters being labeled in a negative manner based on their appearances.
Explanation: they both are being labeled in a negative manner so that's your answer your welcome
write the name and the formula of the compound formed Potassium and oxygen, and Aluminum and nitrogen.
Answer:
K2O Potassium oxide
Explanation:
La columna de la izquierda corresponde a los tipos de sales y la columna derecha a los tipos de fórmula que presentan. Relacionar con el mismo COLOR las parejas correspondientes. 1. Hidracidas a. MX 2 Acidas b. MXO 3. Oxacidas c. MHXO 4. Basicas d. M(OH)XO
Answer:
1. Hidracidas a. MX
2 Acidas c. MHXO
3. Oxacidas b. MXO
4. Basicas d. M(OH)X
Explanation:
¡Hola!
En este caso, de acuerdo con el concepto de sal, la cual está generalmente dada por la presencia de al menos un metal y un no metal, es posible encontrar cuatro tipos de estas; hidrácidas, oxácidas, básicas y ácidas, en las que las primeras dos son neutras pero la segunda tiene presencia de oxígeno, la tercera tiene iones hidróxido adicionales y la cuarta iones hidrógeno de más.
Debido a la anterior, es posible relacionar cada pareja de la siguiente manera:
1. Hidracidas a. MX
2 Acidas c. MHXO
3. Oxacidas b. MXO
4. Basicas d. M(OH)XO
En las que M se refiere a un metal, X a un no metal, H a hidrógeno y O a oxígeno.
¡Saludos!
Which process, in order, would be necessary for this sequence of the rock cycle:
rock → metamorphic rock → igneous rock
Heat and pressure → melting → cooling
Weathering and erosion → compaction → weathering and erosion
Melting → cooling → melting → erosion
Cooling → melting → cooling → weathering and erosion
Answer:
may be the answer is Heat and pressure - melting - cooling
The titration should be stopped when the solution in the flask changes color and the new color remains even when the solution is gently shaken. True False
The above given statement is true.
What is solution?A homogeneous mixture comprised of two or more components is referred to as a solution. Because they are consistently scattered at the molecular or ionic level, the components in a solution are evenly mixed and have a constant composition.
Until the reaction between the two solutions is complete, a solution of known concentration is gradually added to a solution of unknown concentration in a titration. The endpoint, or point at which the reaction is finished, is often identified by a color change that takes place after an indicator is added to the solution being titrated.
The reaction has achieved its endpoint when the solution in the flask changes color, and the new color persists even after the solution is gently shaken. At this time, the titration should be halted. By doing this, it is possible to precisely determine the concentration of the unknown solution and the volume of titrant added to the solution.
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A population of Esherichia coli is given time to grow for eight generations. The final population is 1,996,800 cells. What was the initial population in cells?
Answer:
7800 cells
Explanation:
The number of Escherichia coli cells N after n generations is given by
N = 2ⁿ × N₀ where N₀ = initial population
Now making N₀ subject of the formula, we have
N₀ = N/2ⁿ
Since n = 8 and N = 1,996,800 cells, substituting the values of the variables into the equation, we have
N₀ = N/2ⁿ
N₀ = 1,996,800 cells/2⁸
N₀ = 1,996,800 cells/256
N₀ = 7800 cells
So, the initial population of Escherichia coli cells is 7800 cells.
How much pressure should an airbag have?
Answer:
It should have about 70-80 pounds of air pressure.
Answer:
5 lbs is what I read on the internetluv </3
Answer This Picture..
Answer:
red and blue
Explanation:
1. How many molecules of S2 gas are in 756.2 L?
a. 2.032 x 1025 molecules S,
b. 3.022 x 1023 molecules S,
c. 4.302 x 10 molecules S
d. 8.203 x 10' molecules S2
Answer: There are [tex]2.032 \times 10^{25}[/tex] molecules [tex]S_{2}[/tex] gas are in 756.2 L.
Explanation:
It is known that 1 mole of any gas equals 22.4 L at STP. Hence, number of moles present in 756.2 L are calculated as follows.
[tex]Mole = \frac{Volume}{22.4 L}\\= \frac{756.2 L}{22.4 L}\\= 33.76 mol[/tex]
According to mole concept, 1 mole of every substance contains [tex]6.022 \times 10^{23}[/tex] molecules.
Therefore, molecules of S present in 33.76 moles are calculated as follows.
[tex]1 mol = 6.022 \times 10^{23}\\33.76 mol = 33.76 \times 6.022 \times 10^{23}\\= 2.032 \times 10^{25}[/tex]
Thus, we can conclude that there are [tex]2.032 \times 10^{25}[/tex] molecules [tex]S_{2}[/tex] gas are in 756.2 L.
Hey everyone, I'm starting honors chemistry next year and I want to get prepared for the class. What are the basic keys information that I need to know for the subject.
Thanks!
Answer:
hi!
Explanation:
Well, some things I would do is to know the Periodic Table font and back. Know they elements and their class and atomic number and weight. Know how many atoms make up each element and how many protons, neutrons, and elements are in each atom.
a reaction of heating patassium permanganate produces potassium manganate, manganese dioxide and oxygen gas. Heat 15.8 g potassium permanganate until no more oxygen gas is given off. The remaining material has a mass of 14.2 g. What mass of oxygen gas was produced in the reaction?
*CAN SOMEONE HELP ME PLEASE*
Answer:
d
Explanation:
the answer is d is that correct
Suppose that you want to make 12 g of lithium oxide.
What are the minimum masses of lithium and oxygen you will need?
A. Li= 5.6 g O2= 6.4 g
B. Li 6.5 g O2= 4.6 g
C. Li= 0.6 g O2 46.4 g
D. Li= 15.6 g O2 6.4 g
Answer:
A. Li= 5.6 g O2= 6.4 g
Explanation:
Lithium oxide, Li2O, is an oxide that contains 2 moles of Li and 1 mole of O per mole of oxide. To solve this question we must find the mass of each atom in the molecule as follows:
2Li = 2*6.941g/mol = 13.882g/mol
O = 1*16g/mol = 16g/mol
Molar mass Li2O:
16+13.882 = 29.882g/mol
The mass of lithium is:
12g * (13.882g/mol / 29.882g/mol) = 5.6g Li
And the mass of oxygen:
12g * (16g/mol / 29.882g/mol) = 6.4g O
Right answer is:
A. Li= 5.6 g O2= 6.4 g