Answer:
B. 20, 22, 20
Explanation:
The atomic number (Z) of calcium is 20, that is, it has 20 protons.
The mass number (A) of calcium-42 is 42. The mass number is equal to the sum of protons and neutrons. Then,
p⁺ + n⁰ = 42
n⁰ = 42 - p⁺
n⁰ = 42 - 20
n⁰ = 22
Since calcium is electrically neutral, it has the same number of protons (+) and electrons (-). Then, calcium has 20 electrons.
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Question 1
1 pts
Where did most of the heat of the Earth come from at its formation?
O Seismic waves
O Radioactive decay
O Planetesimals crashing into each other
Peridotite xenoliths
Question 2
1 pts
Answer:
radioactive decay
Explanation:
a study reveals that only about half of our planets internal heat stems from natural radioactivity the rest is primordial heat left over from when earth first coalesced from a hot ball of gas dust and other material
which force does the truck use to move the car with it A.push B.pull C.gravity D.Friction
it is push i think to move the car
Answer:
Either A. Push or B.Pull because the truck is either pushing or pulling the car to move it. So it depends on if it's pushing or pulling the car.
Explanation:
exhibits the highest intermolecular
forces of the states of matter.
Answer:
Solid
Explanation:
In solid there are strong intermolecular forces present as compared to liquid and gas. This is why solid are in more packed form as compared to liquid and gas. In liquid and gas intermolecular forces are week that's why molecules are away from each other and occupy more space.
Properties of gases:
Molecule of gases randomly move everywhere and occupy all available space.
Gases don't have definite volume and shape and take the shape and volume of container in which it present.
Their densities are very low as compared to the liquid and solids.
Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.
The very weak inter molecular forces are present between gas molecules.
Properties of Liquid:
Liquid have definite volume but don't have definite shape.
Their densities are high as compared to the gases but low as compared to the solids.
In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.
Properties of solids:
Solids have definite volume and shape.
In solids molecules are tightly pack and very close to each other.
Their melting and boiling point are every high.
The densities of solids are also very high as compared to the liquid and gas.
There are very strong inter molecular forces are present between solid molecules.
Answer:
A: Solid
Explanation:
Correct with Acellus
Determine the pH of a 2.0 x 10-2 M Sr(OH)2 solution.
pH of the Sr(OH)₂ solution : 12.6
Further explanationpH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
pH = - log [H⁺]
Sr (OH) ₂ solution is a base with valence 2, so we determine the pOH from the OH ion concentration - which is expressed by pOH = - log [OH -]. After that we determine the pH value from the relationship:
[H⁺] [OH⁻] = Kw=10⁻¹⁴
pH + pOH = 14
Sr(OH)₂⇒Sr²⁺+2OH⁻
From equation [Sr(OH)₂] : [OH⁻]=1 : 2, so [OH⁻]=
[tex]\tt [OH^-]=2\times 2.10^{-2}=4.10^{-2}~M[/tex]
[tex]\tt pOH=-log[OH^-]\\\\pOH=-log~4.10^{-2}\\\\pOH=2-log~4\rightarrow 1.398 \\\\pH+pOH=14\\\\pH=14-1.398\\\\pH=12.6[/tex]
pH is the measurement of the concentration of hydrogen or hydronium ion in an aqueous solution. The pH of strontium hydroxide is 12.6.
What is pH?The pH is the potential of hydrogen or the negative log of its concentration.
First, calculate the pOH of strontium hydroxide by:
[tex]\begin{aligned} \rm pOH &= \rm - log [OH ^{-}]\\\\&= \rm -log [4\times10^{-2}]\\\\&= 1.398\end{aligned}[/tex]
Now, calculate pH from pOH as:
[tex]\begin{aligned}\rm pH &= 14 - \rm pOH\\\\&= 14 - 1.398\\\\&= 12.6\end{aligned}[/tex]
Therefore, 12.6 is the pH of strontium hydroxide.
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Could someone pls help me :)
liquid 1 and 2 have the same color and mass so the answer would be liquid 1 and 2
Explanation:
hope this is helpful
Because of gravity, your weight
on the Moon
A. would be the same as it is on Earth
B. would be less than your weight on Earth
C. would be more than your weight on Earth
D. and your mass would be less than it is on Earth
Answer:
the answer is b
Explanation:
brcause the gravutational pull on the moon is lower than on earth...
Suppose you wish to determine the order of the reaction. You initially measure a rate, r0, given some arbitrary concentration of reactants. You then proceed to double the amount of A in the reaction (keeping B the same) and find that the rate is now 2r0. In a reciprocal experiment, you double the amount of B (A same as initial) in the reaction and measure a rate of 8r0. What is the order of this reaction
Answer:
See explanation
Explanation:
Now taking A, we can see that if we double the amount of A while keeping the amount of B constant, the rate of reaction doubles, hence we can write;
2^n = 2^1
hence n =1
For B, when the amount of B is doubled while keeping the amount of A constant, the rate of reaction increases eight times. Hence we can write;
2^n = 8
2^n = 2^3
n=3
Hence this reaction has an overall order of 1 + 3 = 4
So we can write;
rate =k[A] [B]^3
Which of these sentences probably comes from a work of classic literature?) PLEASE HELP ILL GIVE YOU BRAINLEIST!
A. The greedy man was harsh as winter, and had never done a generous deed in his long life; he was a hermit.
B. The man who refused to share with those in need had never felt the warmth that comes from giving.
C. The most selfish man in town was one who lived alone and never had visitors of any sort, except maybe lawyers.
D. The miser was hard and sharp as flint, from which no steel had ever struck out generous fire; he was as solitary as an oyster.
The sentences that probably comes from a work of classic literature are:
The most selfish man in town was one who lived alone and never had visitors of any sort, except maybe lawyers. The miser was hard and sharp as flint, from which no steel had ever struck out generous fire; he was as solitary as an oyster.What types of books are regarded as classics?The great literary works of Greek, Roman, and other prehistoric civilizations are referred to as classical literature. Classical literature includes the writings of Homer, Ovid, and Sophocles. The phrase isn't just applicable to books. It can also incorporate other types of writing, such as epic, lyric, tragedy, comedy, and pastoral.
Classical literature enables us to take a profound plunge into the lives, worldviews, and mindsets of individuals we have never met, to travel to unfamiliar settings, and to comprehend eras we will never be able to experience ourselves.
Therefore, option C and D are correct.
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Amino acids are the building blocks of proteins. The simplest amino acid is glycine (H2NCH2COOH). Draw a Lewis structure for glycine. (Hint: The central atoms in the skeletal structure are nitrogen bonded to carbon, which is bonded to another carbon. The two oxygen atoms are bonded directly to the right-most carbon atom.) Draw the molecule by placing atoms on the grid and connecting them with bonds. Include all hydrogen atoms and nonbonding electrons.
Answer:
Explanation:
The lewis structure (indicating all the atoms and patterns provided as hint in the question) of glycine can be seen in the attachment below. While the chemical structure of glycine can be seen below
H
|
H₂N - C - C =O
| \
H OH
The structure (of glycine) above provides a "fair idea" of how the lewis structure will be.
3. Using the solubility of ionic compounds table and/or the solubility rules,
list 3 substances that will NOT form a solution with water? (Hint:
identify substances that are insoluble with water)
Which force acts on falling objects to oppose gravity?
pull
terminal velocity
air resistance
acceleration
Answer:pull
Explanation:
Help! Can someone please explain and break down the answers to both? I’m so confused!
1) The moles of H2O that f am be obtained from 15.0mL of 0.250 M HCl
2) the volume of 0.150 M KMnO4 needed to replaced 1.85 mol MnCl2
when coal goes through combustion it releases nitrogen and sulpur into the air in the form of what
Answer:
Over time, the plant matter transforms from moist, low-carbon peat, to coal, All types of coal also contain sulfur, which, when burned, releases toxic air pollution. Sulfur All this coal comes from mines, which are either underground or run on diesel—a major source of air toxins, nitrogen oxide, and soot.
butane
methane
ethane
propane
Given
the structure of the alkanes
Required
match the image to the name
Solution
Alkanes are saturated hydrocarbons with all of the carbon bonds being single bonds
General formula:
[tex]\large {\boxed {\bold {C_nH_2n + 2}}}[/tex]
If we look at the picture, we define the black atom as Carbon and the branch is Hydrogen
To determine the name of the alkane, all we have to do is count the number of Carbon atoms
Butane : C₄H₁₀ : 4 C atoms
Methane : CH₄ : 1 C atom
Ethane : C₂H₆ : 2 C atoms
Propane : C₃H₈ : 3 C atoms
Atoms of the same element can have different properties. ( true or false )
Answer:
Atoms of the same element have the same chemical properties. The only differences between atoms of the same element are the number of neutrons in the nucleus and the atomic weight of each isotope. false
Answer:
False
Explanation:
Different elements can have different properties, but not atoms of the same element
Identify the reaction type shown and describe the clues
that were used to identify it.
NHạNO3 → Nz0 + 2H,0
3 Helppppp!!
Answer:
Decomposition reaction.
There's heating of solid Ammonium nitrate to form di nitrogen oxide and water
1.86 g of ethanol reacts with 10.0 g of oxygen. What is the total volume of gas present (in L) after the reaction is complete, assuming the reaction takes place at 1.00 atm and 25oC?
Answer:
See explanation
Explanation:
The equation of the reaction is;
C 2 H 6 O(l) + 3 O 2 (g) → 2 CO 2 ( g ) + 3 H 2 O(l )
Next we have to determine the limiting reactant, this reactant gives the least number of moles of product.
Number of moles of C 2 H 6 O = mass/molar mass = 1.86g/ 46.07 g/mol = 0.04 mols
From the equation;
1 mol of ethanol yields 2 mols of CO2
0.04 moles of ethanol yields 0.04 * 2/1 = 0.08 mols of CO2
For water;
1 mol of ethanol yields 3 mols of water
0.04 moles of ethanol yields 3 * 0.04/1 = 0.12 mols of water
Also;
Number of moles of oxygen= 10g/32g/mol = 0.31 moles
3mols of O2 yields 2 moles of CO2
0.31 moles of O2 yields 0.31 * 2/3 = 0.21 moles of CO2
For water;
3 moles of O2 yields 3 moles of water
0.31 moles of O2 yields 0.31 * 3/3 = 0.31 moles of water
Hence ethanol is the limiting reactant.
From PV=nRT
Volume of CO2 is;
V = nRT/P
V = 0.08 * 0.082 *298/1 = 1.95 L
Volume of water;
V = nRT/P
V= 0.12 * 0.082 * 298/1
V= 2.93 L
Total volume of gases after reaction = 1.95 L + 2.93 L = 4.88 L
Balance the chemical equations.
1FeCl3 + KOH → Fe(OH)3 + KC1
Answer:
FeCl3 + 3KOH → Fe(OH)3 + 3KCl
Explanation:
how can use a BIPHASIC LIQUIDS
Answer:
BIPHASIC LIQUIDS are used ear cleaning, to softening the wax so that mild infections can be treated.
Explanation:
BIPHASIC LIQUIDS are liquids that contain two immiscible phases, one is suspension and the other is emulsion. In suspension, the finely solid are dispersed in a liquid or semi solidwhich is use for medicament
The emulsion consist of immiscible liquids, one is dispersed in globules.
They are used ear cleaning, to softening the wax so that mild infections can be treated.
The percent ionization of a 0.350 M HC,H,O2 solution. Ka(HC2H302)
Answer:
The answer is 56
Explanation:
i need points
Look at the following chemical equation.
10Ag + S = 8Ag S
What is true about this chemical equation? (Hint: The reactant is the substance at the start of a chemical reaction.
The product is the substance at the end of the chemical reaction.
A.It is unbalanced because the number of reactants is less than the number of products.
IB.t is balanced because the products contain the same number of sulfur (S) atoms as the reactants.
C.It is balanced because the mass of the reactants is equal to the mass of the products.
D.It is unbalanced because the products contain fewer silver (Ag) atoms than the reactants.
Answer: I think it is D
Explanation:
a cup of liquid is measured to have a temperature of 290 Celsius, what would that be in the Kelvin scale
Answer:
795k
Explanation:
C÷5=k-273÷9
290÷5 = k - 273 ÷ 9
k = 795
An elemental metal contains how many types of atoms?
a. 1
b. 2
c. 3
d. 4
Answer:
a
Explanation:
all elemental metals are made up of only one type of element
Answer:
It is 1.
Explanation:
How many oxygen atoms are there in one formula of AI2(SO4)3?
There are 12 atoms of Oxygen, since 3 times 4 is 12.
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Question 1 (3 points)
(01.01 LC)
Which of the following objects will exert the greatest gravitational force on a box, if the distance between them remains the same? (3 points)
Оа
2 kg mass
Ob
4 kg mass
Ос
6 kg mass
8 kg mass
The following objects will exert the greatest gravitational force on a box⇒ 8 kg mass
Further explanationGravity is a force that arises because of the attraction between objects with mass.
The magnitude of this attraction is proportional to the mass of the object.
The greater the mass of the object, the greater the gravitational force
Relationships can both be stated in
Newton's Gravity Law:
[tex]\rm F=G.\dfrac{m_1.m_2}{r^2}[/tex]
with F = gravitational force,
G = gravitational constant,
m1, m2 = mass of object,
r = distance between two objects.
The distance-r and mass of the box(m₁) are the same, then the largest object's mass (m₂)exerts a large gravitational force, because the gravitational force is directly proportional to the mass of the two objects
Name one way that the scientific community has honored Mendeleev’s contribution to science.
Answer:
Mendeleev's greatest contribution to science is certainly the Periodic Table of Elements, which says the properties of basic elements repeat periodically when they are arranged by their atomic number. He made the discovery in 1869 during his work on the award-winning textbook on chemistry basics.
Inventions: Periodic table, Pyrocollodion
Explanation:
*Hope this helps*
Answer:
Mendeleev's greatest contribution to science is certainly the Periodic Table of Elements, which says the properties of basic elements repeat periodically when they are arranged by their atomic number. He made the discovery in 1869 during his work on the award-winning textbook on chemistry basics.
Inventions: Periodic table, Pyrocollodion
Explanation:
Now, let's solve our problem using Boyle's Law:
A gas that exerts a pressure of 151 mm Hg in a
container with a volume of
L will exert a
pressure of 166 mm Hg when transferred to a
container with a volume of 0.532 L.
[?]L
Assume that the number of moles and the
temperature remain constant.
Answer:
V₁ = 0.585 L
Explanation:
Given data:
Initial pressure = 151 mmHg
Initial volume = ?
Final pressure = 166 mmHg
Final volume = 0.532 L
Solution:
The given problem will be solved through the Boyle's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
151 mmHg × V₁ = 166 mmHg × 0.532 L
V₁ = 166 mmHg × 0.532 L / 151 mmHg
V₁ = 88.312mmHg .L /151 mmHg
V₁ = 0.585 L
I use a psychrometer to measure the relative humidity on a starry
summer night. My dry-bulb temperature is 18 degrees Celsius, and my
wet-bulb temperature is 19 degrees Celsius. What is the relative
humidity, in %?
The relative humidity on a starry summer night is determined as 91%.
Dry bulb depression temperature
The dry bulb depression temperature is calculated as follows;
ΔT = 19⁰C - 18⁰C = 1⁰C
at dry bulb temperature of 18⁰C and depression temperature of 1⁰C, the relative humidity is determined as 91%.
Thus, the relative humidity on a starry summer night is determined as 91%.
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In the acetylene torch, acetylene gas (C2H2)(C2H2) burns in oxygen to produce carbon dioxide, water, and energy: 2C2H2(g)+5O2(g)⟶Δ4CO2(g)+2H2O(g)2C2H2(g)+5O2(g)⟶Δ4CO2(g)+2H2O(g) You may want to reference (Pages 241 - 243) Section 7.7 while completing this problem. Part A How many moles of O2O2 are needed to react with 1.85 molmol of C2H2C2H2? Express your answer to three significant figures and include the appropriate units. nn(O2O2) = nothingnothing SubmitRequest Answer
Answer:
4.63 mol
Explanation:
Step 1: Write the balanced complete combustion reaction of acetylene
2 C₂H₂(g) + 5 O₂(g) ⟶ 4 CO₂(g) + 2 H₂O(g)
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of C₂H₂ to O₂ is 2:5.
Step 3: Calculate the number of moles of O₂ needed to react with 1.85 moles of C₂H₂
We will use the stoichiometric molar ratio.
1.85 mol C₂H₂ × (5 mol O₂/2 mol C₂H₂) = 4.63 mol O₂
If 35.0 g of aluminum changes temperature by 84.0℃, how much heat was absorbed? specific heat of Al = 0.910 J/g℃
40567⁰ kkkkkkkkkkkkkkkkkkkkkkmeow
Explanation:
cuz I got a 100