Answer:
4.000 hope this helps :)
rare earth elements plz
Answer:
Rare earth elements are lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium - that appear in low concentrations in the ground.
Explanation:
The rare earth elements (REE) are a set of seventeen metallic elements. These include the fifteen lanthanides on the periodic table plus scandium and yttrium. Rare earth elements are an essential part of many high-tech devices.
name the gas which is formed when coal is heated in the absense of air
Answer:
Coke
Explanation:
A solid fuel formed by heating coal in the absence of air is coke. Coke is black colored, tough porous substance. It is pure carbon.
SOMEONE HELP ASAP I NEED TO FIND AN ANSWER
Answer:
A) Q + XZ = X + QZ is a single displacement reaction.
B) Q + Z = QZ is a synthesis reaction
C) QT = Q + T is a decomposition reaction
D) QT + XZ = QZ + XT is double replacement reaction.
Explanation:
A) Q + XZ = X + QZ
This is a single displacement reaction because it is one in which one element is substituted for another one in a compound. In this case X is substituted for Q.
B) Q + Z = QZ
This is a synthesis reaction because Q and z combine to form a single product QZ.
C) QT = Q + T
This is a decomposition reaction because the compound QT breaks down to form 2 simpler substances Q and T.
D) QT + XZ = QZ + XT
Thus is a double replacement reaction because QT and XZ have exchanged cations to form new compounds QZ and XT
What is a reaction rate
Answer:
Explanation:
A reaction rate is the measure of the change in concentration of the disappearance of reactants or the change in concentration of the appearance of products per unit time
In the chemical reaction between aqueous magnesium chloride and sodium metal, what chemical amount (mol) of magnesium metal can be precipitated (produced) with 12.6 mol of sodium metal?
Answer:
6.3moles
Explanation:
The balanced equation of the reaction described above between aqueous magnesium chloride and sodium metal is as follows:
MgCl2(aq) + 2Na(s) → 2NaCl(aq) + Mg(s)
From the above equation, 2 moles of sodium metal (Na) produces 1 mole of Magnesium metal (Mg)
Hence, 12.6 mol of Na will produce (12.6/2) mol of Mg.
12.6/2 = 6.3moles of Mg metal.
1.1 Define the concept risky behaviour?
Answer:
Risky behavior or risk-taking behavior is defined according to Trimpop (1994) as “any consciously, or non-consciously controlled behavior with a perceived uncertainty about its outcome, and/or about its possible benefits, or costs for the physical, economic or psycho-social well-being of oneself or others.” In addition to this broad definition, there are other definitions of risky behavior depending on the field of research. While in the economic view, risk is defined in terms of the variability of possible monetary outcomes, in the clinical literature, the risk is generally defined as exposure to possible loss or harm (Schonberg, Fox, & Poldrack, 2011). Turner et al. (2004) described risk-taking behavior further as either a socially unacceptable volitional behavior with a potentially negative outcome in which precautions are not taken, such as speeding, drinking and driving, drugs abuse, unprotected sex and so on.
The osmotic pressure of a solution formed by dissolving 0.231 g of the protein in 150 mL of water at 298 K is found to be 2.054 torr.
Answer:
13924g/mol is the molar mass of the protein
Explanation:
What is the molar mass of the protein.
The osmotic pressure of a solution, π, is defined as:
π = c*R*T
Where π is osmotic pressure = 2.054torr* (1atm/760torr) = 2.70x10⁻³atm
c is molar concentration of the protein,
R is gas constant = 0.082atmL/molK
And T is absolute temperature = 298K
Solving the molar concentration:
c = π / RT
c = 2.70x10⁻³atm / 0.082atmL/molK*298K
c = 1.106x10⁻⁴ moles protein / L
The moles of protein in 150mL = 0.150L:
0150L * (1.106x10⁻⁴ moles protein / L) = 1.659x10⁻⁵ moles protein
The molar mass is the ratio of mass and moles:
0.231g / 1.659x10⁻⁵ moles protein =
13924g/mol is the molar mass of the proteinlos metales se oxidan
According to the kinetic-molecular theory, the average kinetic energy of gas particles depends on which factor?
Answer:
Temperature.
Explanation:
Kinetic molecular theory of gases states that gas particles exhibit a perfectly elastic collision and are constantly in motion.
According to the kinetic-molecular theory, the average kinetic energy of gas particles depends on temperature.
This ultimately implies that, the average kinetic energy of gas particles is directly proportional to the absolute temperature of an ideal gas. Thus, an increase in the average kinetic energy of gas particles would cause an increase in the absolute temperature of an ideal gas.
Temperature can be defined as a measure of the degree of coldness or hotness of a physical object. It is measured with a thermometer and its units are Celsius (°C), Kelvin (K) and Fahrenheit (°F).
State the name(s) of the sub-atomic particle(s) that have/has a positive charge. Answer with the name of the particle(s) only.
A. Neurons
B. Protons
C. Electrons
Answer:
protons because they have the most positive charge
tolong saya jawab yahhh
(i) Liang - liang stoma lebih banyak di bahagian bawah daun berbanding di bahagian atas permukaan daun.
(ii) Struktur X berfungsi mangawal pembukaan dan penutupan liang stoma
Please help me with this in the picture I need 8 thing wrong and 8 what should they do right
Which two of the following changes of state involve solids?
Select two (2) answers
A. melting
B. boiling
C. freezing
D. evaporating
Answer:
Answer is A... Melting and freezing
What is pH?
O A. A measurement indicating how acidic a solution is
B. A concentration of total ions dissolved in solution
C. A level of dissolved gases that are in solution
O D. A component of solutions that makes them acidic
Answer:
Awnser is A
Explanation:
Answer:
Hello There!!
Explanation:
The answer is↬O A. A measurement indicating how acidic a solution is.
hope this helps,have a great day!!
~Pinky~
If 3.02 g of CuNO3 is dissolved in water to make a 0.560 M solution, what is the volume of the solution in milliliters?
Answer: The volume of the solution is 28.75 mL
Explanation:
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (mL)}}[/tex] .....(1)
Given values:
Molarity of copper nitrate = 0.560 M
Given mass of copper nitrate = 3.02 g
Molar mass of copper nitrate = 187.56 g/mol
Putting values in equation 1, we get:
[tex]0.560=\frac{3.02\times 1000}{187.56\times \text{Volume of solution}}\\\\\text{Volume of solution}=\frac{3.02\times 1000}{187.56\times 0.560}=28.75mL[/tex]
Hence, the volume of the solution is 28.75 mL
which is an example of the force of attraction between two obects that have mass?
Answer:
gravity
Explanation:
Gravity is an example of the force of attraction between two objects that have mass.
What point A on the phase diagram called?
liquid
(374°C/218 atm)
A
solid
pressure (atm)
gas
temperature (°C)
OA.
the melting point
OB.
the boiling point
Ос.
the freezing point
OD
the critical point
OE.
the triple point
Answer:
D) the critical point
Explanation:
Point A is the critical point in phase diagram. This is the highest temperature and pressure at which a pure material can exist in vapor/liquid equilibrium. Pretty cool!
Help please I’ll give you brainless
Answer:
Step 9
Explanation:
The reason i selected step 9, is if you take a look at the picture hes setting up a funnel,With filter paper and if you take a look at number ''9'' questions it says set up a funnel, filter paper and filter flask which is shown in the picture on top that's how i got my answer
Se trata 50 g de aluminio que posee 10% de impurezas con suficiente cantidad de ácido sulfúrico ¿qué peso de sulfato de aluminio se obtiene si el porcentaje de rendimiento fue de 70%? P.A. (uma): Al: 27, S = 32, O = 16
Respuesta:
199.5 g
Explicación:
Paso 1: Escribir la reacción balanceada
2 Al + 3 H₂SO₄ ⇒ Al₂(SO₄)₃ + 3 H₂
Paso 2: Calcular la masa pura de 50 g de Al
Aluminio tiene 10% de impurezas, es decir, 10% de 50 g = 5 g. Luego, tiene 50 g - 5 g = 45 g de Al puro.
Paso 3: Calcular la masa teórica de Al₂(SO₄)₃ obtenida a partir de 45 g de Al
La relación de masas de Al₂(SO₄)₃ a Al es 342:54.
45 g Al × 342 g Al₂(SO₄)₃/54 g Al = 285 g Al₂(SO₄)₃
Paso 4: Calcular la masa real de Al₂(SO₄)₃ obtenida
El rendimiento de la reacción es de 70%.
285 g × 70% = 199.5 g
Jason combines the two intermediate steps shown. 2 equations. First: upper N subscript 2 (g) plus upper O subscript 2 (g) right arrow 2 upper N upper O (g). Second: 2 upper N upper O (g) plus upper O subscript 2 (g) right arrow 2 upper N upper O subscript 2 (g). Which best describes what Jason should do with the oxygen molecules?
Answer:
The molecules of oxygen should be placed as reactants in the equation.
Explanation:
1: N₂ + O₂ → 2NO
2: 2NO + O₂ → 2NO₂
complete reaction:
N₂ + 2O₂ → 2NO₂
In both intermediate equations' oxygen is used as reactant because the end product is the product of the combination of nitrogen and oxygen. So in the complete or overall reaction, oxygen should also be placed as reactant.We can not place oxygen at the side of products neither we can cancel it because, products can only be obtained at the end of the reaction but according to the equations' oxygen is not the end product of the reaction. But the addition into the reaction (Eq. 2) to make the new product.
Also, we can not cancel it because to cancel out molecules of oxygen should be present at the both sides with same amount in the stoichiometric equation.
Hence, in a balanced chemical equation, oxygen should be written as a reactant by using the correct number of moles.
HELP! HELP! Calculate the value of ΔS⁰ at 298 K.
Answer:
ΔS⁰ = -181.1J/molK
Explanation:
ΔS⁰ of a reaction is defined as the sum of the entropies of the reactants times its reaction coefficient minus the sum of the entropies of the products times its reaction coefficient. For the reaction in the problem:
ΔS⁰ = 2*S{NaCl(s)} - (2*S{Na(s)}+S{Cl2(g)})
ΔS⁰ = 2*72.1J/molK - (2*51.1J/molK + 223.1J/molK)
ΔS⁰ = -181.1J/molKSubtract to find the temperature changes
for the water and the metal.
Answer:
???what metal????????????
How many electron containing orbitals are in an atom of tin ?
Answer:
10
Explanation:
how many electron-containing d orbitals are there in an atom of tin? name the element in the 4th period whose atoms have the same number of highest-energy-level elctrons as tin
10, germanium
Two or more than two atoms with different physical or chemical properties can not combine together to form an element. Therefore, the total number of orbitals containing electrons in an atom of tin are 10 orbitals.
What is element?Element generally consist of atoms or we can atoms combine to form element. Atoms of an element is always same, means all the properties of all atoms of one type of element is same.
The electronic configuration of tin is 1s² 2s² 2p⁶ 3s²3p⁶ 4s² 3d¹⁰ 4p⁶ 5s²4d¹⁰ 5p² or [Kr] 5s² 4d¹⁰ 5p². The total number of orbitals containing electrons in an atom of tin are 10 orbitals. tin an element that belongs to p block of periodic table.
Therefore, the total number of orbitals containing electrons in an atom of tin are 10 orbitals.
To know more about element, here:
https://brainly.com/question/8460633
#SPJ2
How much energy does a 930 nm wave of light have? (The speed of light in a vacuum is 3.00 x 108 m/s, and Planck's constant is 6.626 x 10-34 J·s.)
A. 4.68 x 10^18 J
B. 2.14 x 10^-19 J
C. 1.85 x 10^-31 J
D. 4.21 x 10^35 J
Answer:
B. 2.14 x 10^-19 J
Explanation:
The energy of a wave of light can be obtained using the equation:
E = h*c/λ
Where E is the energy in joules,
λ is wavelength = 930nm = 930x10⁻⁹m
h = Planck's constant = 6.626x10⁻³⁴Js
c = Speed of light = 3.00x10⁸m/s
Replacing:
E = 6.626x10⁻³⁴Js*3.00x10⁸m/s/930x10⁻⁹m
E = 2.14x10⁻¹⁹J
Right option is:
B. 2.14 x 10^-19 J
If one of the reactants in a reaction us Na2O, what is known about the products?
Ok here's the deal
the answer is A: The products will contain exactly 2 Na atoms and 1 O atom.
Explanation:
thank me later space-ex kids
How do the Carnivorous plants survive without soil?
Answer:
A simple answer: Carnivores don't eat plants only flesh. So they would not need soil. But it would be hard for Carnivores to get energy because they get energy indirectly from the animals (herbivores) that they eat. How do they get the energy from a herbivore you might ask. Herbivores eat only plants and that gives the herbivore the plant's energy; but if the herbivore gets eaten, it is indirectly transferred into the Carnivore. Hope this helped!!
Carnivore = only feeds on flesh
Herbivore = eats only plants
Omnivore = eats plants and animals/flesh
Boyle's Law Problems
Charles' Law Problems
Answer:
here are the answers babe. Feel free to ask for more
Increasing the concentration increases the speed of reaction by... increasing the number of collisions between products increasing the amount of energy in the system increasing the number of collisions between reactants lowering the activation energy of the reaction
Answer: increasing the number of collisions between reactants
Explanation:
A reaction is possible due to collisions between the reactants to create products. If we increase the concentration of reactants then that means that we are increasing the molecules of the reactants which would give them more chances to collide and make products.
For instance, using a non-chemistry example, if there are few cars in a large city, the accidents there will be less because the cars will have such space that they wouldn't collide with each other. If the number of cars in the city is increased however, there is now less space and more chances for cars to collide.
The temperature of a sample of liquid water changes from 50°C to 30°C. Which statement best explains the change
that must happen at the molecular level?
The molecules move more quickly and their average kinetic energy increases
The molecules move more bowly and their average kinetic energy decreases
The molecules move more quickly and their average kinetic energy decreases
The molecules move more slowly and their average kinetic energy increases.
Answer:
The molecules move slower than the temp of 50°c and their average kinetic energy decreases.
Explanation:
kinetic energy cannot increase as temperature is reduced. molecules will still move with reduced motion.
What type of nuclear decay is shown by the reaction below?
A. Alpha
B. Gamma
C. Beta
O D. Fission
Answer:
C. Beta
Explanation:
