Answer:
Lanthanide or Lanthanides
Explanation:
sorry if this isent right, but i hope it helps
There are various kind of elements that are present in periodic table. Some elements are harmful, some are radioactive, some are noble gases. Therefore the correct option is Lanthanides and actinides.
What is periodic table?Periodic table is a table in which we find elements with properties like metals, non metals, metalloids and radioactive element arranges in increasing atomic number.
Periodic table is divided into blocks as s block, p block ,d block and f block. There are total two periods of f block elements. The one that comes in 6th period is called Lanthanides and one which is in 7th period is called actinides. Lanthanides and actinides are called inner transition element and contains 14 elements.
Therefore the correct option is Lanthanides and actinides.
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A rectangular block has dimension 20m x10mx5m and mass of 400kg calculate the density of the rectangular block
Answer:
0.4 kg/m^3
Explanation:
v (volume) = 20m x 10m x 5m = 1000 m^3
w (weight) = 400 kg
d (density) = w / v
d = 400 / 1000 = 0.4 kg per cubic meter (kg/m^3)
I apologize if this is a little complex, however all of the math is there, if you're interested then look it over. Otherwise I've provided the answer in the units used for the dimensions and weight provided.
Is anyone good at chemistry if so can someone help me please ?
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Since pH + pOH = 14, given a pOH of 4.53, our pH would be 14 - 4.53 = 9.47. And since the pH is greater than 7, this solution is basic. So, the correct answer choice would be D.
How much energy is needed to evaporate 100g of water
Answer: you would have to remove 80 calories from 1 g of pure water at the freezing point, 0˚ C, to convert it to 1 g of ice at 0˚ C. Explanation:However, 540 calories of energy are required to convert that 1 g of water at 100˚ C to 1 g of water vapor at 100˚ C. This is called the latent heat of vaporization. On the other hand, you would have to remove 80 calories from 1 g of pure water at the freezing point, 0˚ C, to convert it to 1 g of ice at 0˚ C.
Graphite, an allotrope of carbon, is converted into cubic diamond through a process that may take a billion years or longer. As illustrated above, scientists can make synthetic diamonds using a certain process in about one week. However, these synthetic diamonds have carbon atoms in a hexagonal lattice. Diamonds with a carbon atoms in a cubic lattice are not produced even though they are thermodynamically more stable than hexagonal diamond. Which of the following best justifies why the synthetic process produces hexagonal diamond and not the more thermodynamically stable cubic diamond?
a. The amount of energy required to create new bonds between carbon atoms in cubic diamond is much greater than the amount of energy required to create hexagonal diamond.
b. The amount of energy required to create new bonds between carbon atoms in cubic diamond is much smaller than the amount of energy required to create hexagonal diamond.
c. The activation energy needed to form cubic diamond is much less than the activation energy needed to form hexagonal diamond.
d. The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond.
Answer:
The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond.
Explanation:
The activation energy refers to the minimum energy that reacting species must possess before they can undergo a particular chemical reaction.
This implies that if species do not possess the activation energy, they hardly undergo a given reaction. The activation energy is the barrier between reactants and products.
Hence, a reaction that has a very high activation energy occurs slowly or may not even occur. The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond hence the synthetic process produces hexagonal diamond and not the more thermodynamically stable cubic diamond.
If 75 g. of Potassium Chloride (ionic compound) is dissolved in 250 grams of
water, what will be the freezing point of the solution? Kf = 1.86
Answer:
[tex]T_{f,sol}=-15.0\°C[/tex]
Explanation:
Hello there!
In this case, for these problem about the colligative property of freezing point depression, it is possible set up the following equation:
[tex]T_{f,sol}-T_{f,water}=-i*m*Kf[/tex]
Whereas the van't Hoff's factor, i, is 2 since KCl is ionized in two ions (K+ and Cl-); and the molality (m) of the solution is computed by:
[tex]m=\frac{75g*\frac{1mol}{74.55g} }{250g*\frac{1kg}{1000g} } \\\\m=4.02mol/kg[/tex]
Thus, since the freezing point of water (ice) is 0°C, we obtain the following freezing point of the solution by plugging in:
[tex]T_{f,sol}=-(2)(4.02mol/kg)(1.86\°C/mol*kg)\\\\T_{f,sol}=-15.0\°C[/tex]
Best regards!
Which product forms from the synthesis reaction between lithium (Li) and oxygen (O)?
A. Li2O
B. LiO
C. LiO2
D. Li2O2
Answer:
A Li2O
Explanation:
Li has a 1+ charge and O has a 2- charge so to balance the charges there needs to be 2 Li for every 1 O
The product forms from the synthesis reaction between lithium (Li)and oxygen (O) is Li₂O. The correct option is A.
What is synthesis reaction?
Synthesis reaction is the reaction when two or more products combine to form a single product.
An example of a synthesis reaction is the combination of sodium (Na) and chlorine (Cl) to produce sodium chloride (NaCl).
Thus, the correct option is A. Li2O.
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what part of of the universe is less than 1 km in diameter
Answer:
Meteoroids
Explanation:
Meteoroids are the elements of the universe that have the smallest diameter among all elements, reaching less than 1 km in diameter. They are any rocky or metallic body, which exists in space and does not reach more than 100 meters. It is common for meteoroids to fall to earth, but their impact is not as destructive as the impact of other space bodies, due to their tiny size.
15 The Following statement describes which body system? It also produces blood cells, and stores calcium. It regulates endocrine as well. This specific system uses all bones & joints in your body. A. The Lymphatic System B.The Muscular System C.The Reproductive System D.The Skeletal System
Please disregard this
well i need points
Explanation:
thanks
What product(s) would be formed when these are the reactants? BaF2 + Cl2
Help help help :/
Please
Calculate the concentration of H3O⁺ in a solution that contains 1.8 × 10-5 M OH⁻ at 25°C. Identify the solution as acidic, basic, or neutral. A. 5.5 × 10-10 M, acidic B. 9.2 × 10-1 M, acidic C. 5.5 × 10-10 M, basic D. 1.8 × 10-10 M, neutral
Answer:
A. 5.5 × 10⁻¹⁰ M, acidic
Explanation:
Step 1: Given data
Concentration of H₃O⁺: 1.8 10⁻⁵ M
Step 2: Calculate the concentration of OH⁻
We will use the ionic product of water.
Kw = 1.0 × 10⁻¹⁴ = [H₃O⁺] × [OH⁻]
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 1.0 × 10⁻¹⁴/1.8 10⁻⁵ = 5.5 × 10⁻¹⁰ M
Step 3: Determine if the solution is acidic, basic or neutral
If [H₃O⁺] > 10⁻⁷ M, the solution is acidic.If [H₃O⁺] = 10⁻⁷ M, the solution is neutral.If [H₃O⁺] < 10⁻⁷ M, the solution is basic.Then, the solution is acidic.
6. What is the number of moles of KF in a 29 gram sample?
a. 59.0 mols
C. 2.0 mols
b. 470 mols
d. 1684.9 mols
What are characteristics of absorption spectra? Check all that apply.
Light is absorbed, which produces characteristic lines.
| Light is emitted, which produces characteristic lines.
Lines are dark on a visible light background.
Lines are brightly colored on a black background.
Lines are produced by electrons being excited.
Lines are produced from electrons returning to a lower energy level.
Answer:
Light is absorbed, which produces characteristic lines.
Lines are dark on a visible light background.
Lines are produced by electrons being excited.
Explanation:
Edg
The characteristics of absorption spectra light is absorbed, which produces characteristic lines, lines are dark on a visible light background and Lines are produced by electrons being excited.
What is absorption spectra?The term "absorption spectroscopy" applies to spectroscopic methods that assess how much radiation interacts with a sample and is absorbed as a proportion of frequency or wavelength. The sample takes in photons, meaning energy, from the emitting field.
What are electrons?The electron would be a subatomic particle with a negative one fundamental charge electric charge. Due to their lack of components or substructure, electrons, which have become part of the lepton particle family's first generation, could be typically regarded to be elementary particles.
The percentage of incoming electromagnetic energy that a material absorbs across a variety of frequencies is displayed in the material's absorption spectrum. In a way, an emission spectrum would be the converse of an absorption spectrum.
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What is the pH of 0.42M aniline?
Answer:
Kb=x^2/0.42-x (eqn to calculate)
basicity (pkb) 9.3
Explanation:
The half-life of I-37 is 8.07 days. If 25 grams are left after 40.35 days, how many grams were in the original sample?
Answer:
800 g
Explanation:
We can express the decay of I-37 using the formula:
Final Mass = Initial Mass * [tex]0.5^{\frac{Time}{Half-Life} }[/tex]We input the data:
25 g = Initial Mass * [tex]0.5^{(\frac{40.35}{8.07})}[/tex]And solve for Initial Mass:
25 g = Initial Mass * [tex]0.5^{5}[/tex]25 g = Initial Mass * 0.03125Initial Mass = 800 gMeaning that out 800 grams of I-37, only 25 will remain after 40.35 days.
(d) Other
sugar molecules become
_____ and are carried away from the crystal.
the force of attraction is
Answer:
liquid
Explanation:
defiantly
Please help
I need to turn in in 5 min
<3
Please answer this question correctly
Answer:
a d c a b b
Explanation:
22 Which of the following statements is true for all loving organisms? A. All living organisms are made of one or more cells with a cellular membrane and have a cell wall. B. All living organisms are made of one or more cells with a cellular membrane and have a nucleus. C. All living organisms are made of one ore more cells with a cellular membrane and genetic material. D. All living organisms are made of one or more cells with a cellular membrane and have chloroplast
Answer:
C
Explanation:
Ape-x
5. What is the pH of a solution with p0H= 8.5? Is this an acid, base, or neutral?
Answer:
pH = 5.5 and it is an acid
Explanation:
Fr the question given above, the following data were obtained:
poH = 8.5
pH =?
pH + pOH = 14
pH + 8.5 = 14
Collect like terms
pH = 14 – 8.5
pH = 5.5
pH scale reads as follow:
0 to 6 => Acidic
7 => Neutral
8 to 14 => Basic
With the above pH scale, we can conclude that the solution with pH 5.5 is acidic.
0.500 mole of copper(II) sulfate contains
moles of O.
Answer:
2 mol
Explanation:
There are 4 mols of O per one sulfate so since there is only one sulfate you simply times 4 by .5 to get the number of mol
what is the speed of the electromagnetic waves please solve using correct units ill give brainliest.
Answer:
3 m
Explanation:
We'll begin by converting 99.9 MHz to Hz. This can be obtained as follow:
1 MHz = 10⁶ Hz
Therefore,
99.9 MHz = 99.9 MHz × 10⁶ Hz / 1 MHz
99.9 MHz = 99.9×10⁶ Hz
Finally, we shall determine the wavelength. This can be obtained as follow:
Frequency (f) = 99.9×10⁶ Hz
Velocity (v) = 3×10⁸ m/s
Wavelength (λ) =?
Velocity = wavelength × frequency
v = λf
3×10⁸ = λ × 99.9×10⁶
Divide both side by 99.9×10⁶
λ = 3×10⁸ / 99.9×10⁶
λ = 3 m
Thus, the wavelength of the electromagnetic wave is 3 m.
5.50 L of a 0.190 M CaCl2M CaCl2 solution
How do you find Grams?
Answer:
115.891
Explanation:
Molarity is equal to moles/liters so to get moles we multiply molarity by liters, after this we multiply the moles by the total atomic weight of the compound to get grams
PLSSS HELP ASAP!!!!!!!!
Answer:
i-dk but A seems most logical to me
Explanation:
Sally has constructed a concentration cell to measure Ksp for MCln. She constructs the cell by adding 2 mL of 0.05 M M(NO3)n to one compartment of the microwell plate. She then makes a solution of MCln by adding KCl to M(NO3)n. She adds 6.380 mL of the resulting mixture to a second compartment of the microwell plate.
Sally knows n (the charge on the metal ion) = +2
She has already calculated [Mn+] in the prepared MCln solution using the Nernst equation. [Mn+] = 8.279 M
Required:
How many moles of [Cl-] must be dissolved in that compartment?
Answer:
0.1056 mole
Explanation:
As Sally knows that the charge on the metal ion is n = +2
[tex]$MCl_n=MCl_2$[/tex]
In that compartment [tex]$[M^{n+}]=[m^{2+}]=8.279 \ M$[/tex]
The volume of the [tex]$MCl_n$[/tex] taken in that compartment = 6.380 mL
So, the number of moles of [tex]$M^{2+} = 8.279 \times 6.380$[/tex]
= 52.82 m mol
= 0.05280 mol
[tex]$MCl_n \rightarrow M^{n+}+nCl^-$[/tex]
But n = 2
Therefore, moles of [tex]$Cl^-$[/tex] = 2 x moles of [tex]$M^{n+}$[/tex]
= 2 x 0.05282
= 0.1056 mole
Why is there not a constant molar volume for solids and
liquids?
a Solid and liquid particles are packed close together,
b The densities of solids and liquids are variable.
с
The volume of a solid or a liquid has very little
empty space.
d All of the above
Answer:
all of the above
Explanation:
i got the answer right on cK-12
Identify the products formed in this Brønsted-Lowry reaction. HCO−3+HBrO↽−−⇀acid+base
Answer:
[tex]HCO^-_3+HBrO\rightleftharpoons H_2CO_3+BrO^-[/tex]
Explanation:
Hello there!
In this case, according to the Brønsted-Lowry theory of acids, it is possible to realize that HBrO acts as the Brønsted-Lowry acid as it has a free hydrogen to give away to HCO₃⁻ which acts as the Brønsted-Lowry base able to accept the incoming hydrogen; therefore, the Brønsted-Lowry reaction is:
[tex]HCO^-_3+HBrO\rightleftharpoons H_2CO_3+BrO^-[/tex]
Best regards!
In the Brønsted-Lowry reaction between HCO⁻₃ and HBrO, the formed acid is H₂CO₃ and the formed base is BrO⁻.
According to Brønsted-Lowry acid-base theory:
An acid is a substance that donates H⁺.A base is a substance that accepts H⁺.Let's consider the following Brønsted-Lowry reaction.
HCO⁻₃ + HBrO ⇄ acid + base
HBrO can only donate H⁺, so it is an acid.HCO⁻₃ can accept or donate H⁺. Here, it will accept the H⁺ donated by HBrO and behave as a base.The resulting reaction is:
HCO⁻₃ + HBrO ⇄ H₂CO₃ + BrO⁻
H₂CO₃ can donate H⁺ so it is an acid.BrO⁻ can accept H⁺ so it is a base.In the Brønsted-Lowry reaction between HCO⁻₃ and HBrO, the formed acid is H₂CO₃ and the formed base is BrO⁻.
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There are about 26 deuterium atoms for every million hydrogen atoms across the universe, but it is six times as prevalent in the water on Earth and in other solar system bodies. Deuterium has one more ———— than hydrogen.
A. Ionic pair
B. Hydrogen bond
C. Proton
D. Electron
E. Neutron
Answer:
Option E
Deuterium has one more neutron than hydrogen
Explanation:
Deuterium is an isotope of Hydrogen and hence there will variation in the number of neutron
Hydrogen has 0 neutron
Deuterium has 1 neutron and
Tritium has 2 neutron
Thus option E is correct
In the universe, there are approximately 26 deuterium atoms for every million hydrogen atoms. Deuterium has one more neutron than hydrogen.
The correct option is E.
What is deuterium?Deuterium is a stable isotope of hydrogen, whose atomic weight is 2.014.
It is also called heavy hydrogen, and it contains one neutron and one proton.
In nuclear fusion reactors, deuterium is employed as a tracer, while in heavy water moderated fission reactors, it is utilized to slow down neutrons.
Thus, the correct option is E.
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what is the formula for fluoride?
Answer:Chemical formula F −
Molar mass 18.998403163 g·mol−1
Conjugate acid Hydrogen fluoride
Explanation: