Answer:
Helium (He)
Lithium (Li)
Beryllium (Be)
Boron (B)
Explanation:
The chemical elements which have two (2) electron shells are: Lithium and Boron.
Valence electrons can be defined as the number of electrons present in the outermost electron shell of an atom. Thus, valence electrons is typically used to determine whether or not an atom or group of chemical elements found in a periodic table can form a chemical bond with others.
This ultimately implies that, valency is a property that is typically used in determining the chemical properties of chemical elements.
An electron shell can be defined as the outermost shell of an atom around the atomic nucleus. Thus, it is considered to be an orbit accompanied by electrons around the nucleus of an atom.
In Chemistry, the chemical elements which have two (2) electron shells are:
Lithium: it has two electrons in its first shell and one electron in its second shell. Boron: it has two electrons in its first shell and three electrons in its second shell.Read more: https://brainly.com/question/18214726
Can you identify what object is being represented by the model on the right? gear clock battery
Answer:gear
Explanation:just did it right now
Answer: Gear
Explanation: just did it on Edge 2021
what is the Ka of a 0.0592 M solution of hydrofluoric acid (HF) with a pH of 6.90
Answer:
2.7*10^-13
coefficient= 2.7
exponent= -13
Explanation:
Answer: 2.7 x 10^-13
Explanation:
FIRST TO ANSWER GET BRAINLIEST
What is the mass in grams of 3.04 mol of ammonia vapor, NH3?
Answer:
3.04 mol NH3* (17.03 g NH3/ 1 mol NH3)= 51.8 g NH3~
The mass in grams of 3.04 mol of ammonia vapor is 51.68g
What is Mole?The mole is an amount unit similar to familiar units like pair, dozen, gross, etc. It provides a specific measure of the number of atoms or molecules in a bulk sample of matter.
A mole is defined as the amount of substance containing the same number of atoms, molecules, ions, etc. as the number of atoms in a sample of pure 12C weighing exactly 12 g.
Given,
Moles of ammonia = 3.04 moles
Molar mass of ammonia = 14 + 3 = 17
Moles = mass / molar mass
Mass = moles × molar mass
= 3.04 × 17
= 51.68 g
Therefore, mass in grams of 3.04 mol of ammonia vapor is 51.68g
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What is the name for a star that has too low of a mass to start hydrogen fusion?
А.white dwarf
B.black dwarf
C.red dwarf
D. brown dwarf
Answer:
red dwarf
Explanation:
Answer:
D
Explanation:
The balanced chemical equation below represents the formation of magnesium chloride.
Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g)
At STP, what is the total number of liters of hydrogen gas produced when 3.00 moles of hydrochloric acid solution-HCl(aq) is completely consumed?
A.22.4 L
B.11.2 L
C.33.6 L
D.44.8
Answer:
C. 33.6L
Explanation:
Based on the reaction, 2 moles of HCl reacts producing 1 mole of hydrogen.
To solve this question we must find the moles of hydrogen produced using the reaction. Then, with combined gas law (PV = nRT) we can find the volume produced:
Moles H2:
3.00 moles HCl * (1mol H2 / 2mol HCl) = 1.50 moles H2 are produced
Volume:
PV = nRT
V = nRT / P
Where P is pressure = 1atm at STP
V is volume = Our incognite
n are moles of the gas = 1.50 moles
R is gas constant = 0.082atmL/molK
T is absolute temperature = 273.15K
V = nRT / P
V = 1.50mol*0.082atmL/molK*273.15K / 1atm
V = 33.6L
C. 33.6LWhat is Niels Bohr’s Theory
What is the same for all of the drilling sites we examined?
Answer:
the same is what is this question like what did u exame
S8 +O2 = SO8
Given 80 mols of product, find the amount of each reactant in mols.
Answer:
10 moles of S₈
320 moles O₂
Explanation:
S₈ +O₂ → SO₈The balanced equation is:
S₈ + 32O₂ → 8SO₈Now we can convert moles of SO₈ (the product) into moles of each reactant, using the stoichiometric coefficients of the balanced reaction:
80 mol SO₈ * [tex]\frac{1molS_8}{8molSO_8}[/tex] = 10 mol S₈80 mol SO₈ * [tex]\frac{32molO_2}{8molSO_8}[/tex] = 320 mol O₂In order for 80 moles of SO₈ to be produced, 10 moles of S₈ need to react with 320 moles of O₂.
The formula of a compound is M(OH)2 . Given that the Mr of compound is 98 , calculate Ar of M. (Ar of O = 16 , H = 1 ) WITH WOKING OUT
Answer:
The atomic weight Ar, of M is 64
Explanation:
The formula of the given compound is M(OH)₂
Mr, is the molecular weight of a compound and for the given compound, Mr is equal to 98.
Ar, is the atomic weight of the elements in the compound
The molecular weight, Mrof a compound is the mass of one mole mole of that compound. It can be obtained by summing the atomic masses of all elements in that compound. For elements that has more than one atom in the compound, the atomic weight of that element is multiplied by the number of atoms of the element present in the compound and then the sum of the weight of each element gives the molecular weight of the compound.
Onnthe compound above,the atomic weight of the unknown element M, is to be obtained.
Ar of the other elements inn he compound is given : Ar of O = 16, Ar of H = 1.
Molecular weight of the compound, Mr = 98
Calculating for the Ar of M:
(M × 1) + (16 × 2) + (1 × 2) = 98
M +32 + 2 = 98
M + 34 = 98
M = 98 -34
M = 64
Therefore, the atomic weight Ar, of M is 64
True or False: Igneous rocks form from Sediment.
Answer:
true
Explanation:
Answer:
false
Explanation:
Sedimentary rocks form by breaking down other kinds of rocks into small particles and washing or blowing them away; metamorphic rocks form from other rocks and igneous rocks form by melting other rocks. ... Igneous Rocks: form by crystallizing melted material (magma).
For the night yet balanced equation, No + CuCl2 —> Cu + NiCl3, if you started with 12.00 g of nickel and 42.00 g of CuCl2, how much Copper would you expect to produce Perdue
Answer:
19.45g of Cu are expect to be produced
Explanation:
Based on the reaction:
2Ni + 3CuCl2 → 3Cu + 2NiCl3
2 moles of Ni react with 3 moles of CuCl2 to produce 3 moles of Cu
To solve this question we must find the moles of each reactant in order to find the limiting reactant. With the limiting reactant we can find the moles of Cu produced and the mass as follows:
Moles Ni -Molar mass: 58.6934g/mol-
12.00g * (1mol / 58.6934g) = 0.204 moles Ni
Moles CuCl2 -Molar mass: 134.45g/mol-
42.00g * (1mol / 134.45g) = 0.312 moles CuCl2
For a complete reaction of 0.204 moles of Ni are required:
0.204 moles Ni * (3 moles CuCl2 / 2 moles Ni) = 0.306 moles of CuCl2
As there are 0.312 moles, CuCl2 is the excess reactant and Ni is limiting reactant.
Moles Cu:
0.204 moles Ni * (3moles Cu / 2 moles Ni) = 0.306 moles of Cu are produced
Mass Cu:
0.306 moles of Cu * (63.546g / mol) =
19.45g of Cu are expect to be producedWhat is to dissolve?
Answer:
(with reference to a solid) become or cause to become incorporated into a liquid so as to form a solution.
What is the concentration expressed in parts per million of a solution containing 15.0 grams of KNO3 in 65.0 grams of H2O?
Answer:
The concentration will be "[tex]1.88\times 10^5 \ ppm[/tex]".
Explanation:
The given values are:
Mass of solute (KNO₃),
= 15.0 grams
Mass of solvent (H₂O),
= 65.0 grams
The concentration will be:
= [tex]\frac{Mass \ of \ solute}{Mass \ of \ solution}\times 10^6[/tex]
On substituting the values, we get
= [tex]\frac{15.0}{65.0+15.0}\times 10^6[/tex]
= [tex]\frac{15.0}{80}\times 10^6[/tex]
= [tex]0.1875\times 10^6[/tex]
= [tex]187500 \ ppm[/tex]
or,
= [tex]1.88\times 10^5 \ ppm[/tex]
Choose the larger atom from each pair, if possible.
a. Sn or Si,
b. Br or Ga,
c. Sn or Bi,
d. Se or Sn
Answer:
a. Sn or Si ⇒ Sn
b. Br or Ga ⇒ Ga
c. Sn or Bi ⇒ similar in size
d. Se or Sn ⇒ Sn
Explanation:
The larger atom has a larger atomic radius. We have to consider how varies the atomic radius for chemical elements in the Periodic Table. In a group (column), the atomic radius increases from top to bottom while in a period (file), it increases from right to left.
a. Sn or Si ⇒ Sn
They are in the same group. Sn is on the top, so it has a larger atomic radius.
b. Br or Ga ⇒ Ga
They are in the same period. Ga is located at the left so it has a larger atomic radius.
c. Sn or Bi ⇒ similar
They are not in the same group neither the same period. Bi is located more at the bottom, so it would be larger than Sn, but Bi is also at the right side, so it would be smaller than Bi. Thus, they have comparable sizes.
d. Se or Sn⇒ Sn
They are not in the same group neither the same period. Se is located at the top and right side compared to Sn, so Sn is the larger atom.
37.2 moles of hydrogen gas would have what mass?
Your answer
Answer:
74.99g
Explanation:
Mass of a substance can be calculated by using the formula;
mole = mass ÷ molar mass
mass = molar mass × mole
According to this question, 37.2 moles of hydrogen gas is given.
Molar mass of hydrogen gas (H2) = 1.008(2) = 2.016g/mol
mass = 2.016 × 37.2
Mass of H2 = 74.995
Mass = 74.99g
give the equation
CO2(g) <- -> CO2(aq) if we add more CO2(g), carbon dioxide to the air what way would the reaction shift?
Answer:
The equilibrium position shifts to the right.
This is due to excess carbon dioxide which supresses the reaction.
What is the pH of a 0.0001 M aqueous solution of HCI?
If the speed of a wave is 150 m/s and its frequency is 2 Hz, what is its wavelength?
A. 300m
B. 75m
C. 152m
D. 148m
Answer:
75m
Explanation:
Some plants have tap roots; long roots that grow deep into the ground. Where would tap roots for plants be MOST useful?
Answer:
Food storage. The food reserves can be drawn upon to ensure good development of a flower stalk and seeds.
Explanation:
Hope this helps!
Plz help ASAP plz and thx if u help
Answer:
3. c
4. d
5. c
Explanation:
what do atom, molecules, and elements have in common
Answer:
Solids, liquids, gases - all matter - are made up of atoms (or other things, like molecules, that are made from atoms)! ELEMENTS are the kinds of atoms that we can have. Carbon is an element, hydrogen is an element, and so is oxygen. ... Atoms can join together - they form bonds together - to make MOLECULES.
Which best describes what forms in nuclear fission?
two smaller, more stable nuclei
two larger, less stable nuclei
one smaller, less stable nucleus
one larger, more stable nucleus
Answer:
two smaller, more stable nuclei
Explanation:
A. two smaller, more stable nuclei
Explanation:Nuclear fission is the process in which a heavy nucleus is split into two large fragments of comparable mass to form more stable and smaller nuclei. This results in the release of great amounts of energy. Large nuclei are usually less stable, since it takes more energy to hold its structure together, the larger they are.
Here's a photo of Edge just incase.
Which planet contains volcanoes, craters and an atmosphere? Please help
C. Venus is the answer..
how many moles are in 1.25 grams of MgCl2?
Explanation:
No of moles = mass/ molar mass
MgCl2 = 24+35.5*2
= 24+70
= 94 gmol—1
No of moles = 1.25/94
= 0.013 moles
One mole of magnesium chloride weighs 95.21 grams. Therefore, the number of moles in 1.25 grams of the compound is 0.0131 moles.
What is magnesium chloride ?Magnesium chloride is an ionic compound formed by the electron transfer from magnesium metal to the chlorine atoms.
To determine the number of moles of MgCl₂ in 1.25 grams, we need to use the formula:
moles = mass / molar mass
The molar mass of MgCl₂ can be calculated by adding up the atomic masses of its constituent atoms, which are:
Mg: 24.31 g/mol
Cl: 35.45 g/mol (x2, since there are two Cl atoms in MgCl2)
So, the molar mass of MgCl₂ is:
MgCl₂: 24.31 g/mol + 35.45 g/mol x 2 = 95.21 g/mol
Now we can use the formula to calculate the number of moles:
moles = mass / molar mass = 1.25 g / 95.21 g/mol
moles = 0.0131 mol (rounded to four significant figures)
Therefore, there are approximately 0.0131 moles of MgCl₂ in 1.25 grams.
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22.4 L of hydrogen is taken in a cylinder at zero degree Celsius and at one atm. This gas is transferred to a cylinder of 11.2 L capacity without change in temperature. The present pressure and mass of the gas is ....... & ......
Answer:
2 Atm; 2.016 g
Explanation:
Changing the volume without changing the temperature or mass only changes the pressure. Volume and pressure are inversely proportional so halving the volume will double the pressure.
P = 1 Atm, T = 0 °C are "standard" temperature and pressure (STP). The volume of 1 mole of gas is 22.4 L under these conditions. That means the amount of hydrogen gas in the cylinder is 1 mole, so has a mass of 2.016 g.
After the volume reduction, the pressure is 2 Atm, and the mass remains 2.016 g.
Answer:
2 ATM ; 2.016 gAfter the volume of reductionExplanation:
hope it helps
Chemistry help!
Zoom in to see better!!
Answer:
11.9 g of nitrogen monoxide
Explanation:
We'll begin by calculating the number of mole in 6.75 g of NH₃. This can be obtained as follow:
Mass of NH₃ = 6.75 g
Molar mass of NH₃ = 14 + (3×1)
= 14 + 3
= 17 g/mol
Mole of NH₃ =?
Mole = mass /molar mass
Mole of NH₃ = 6.75 / 17
Mole of NH₃ = 0.397 mole
Next, we shall determine the number of mole of NO produced by the reaction of 0.397 mole of NH₃. This can be obtained as follow:
4NH₃ + 5O₂ —> 4NO + 6H₂O
From the balanced equation above,
4 moles of NH₃ reacted to produce 4 moles of NO.
Therefore, 0.397 mole of NH₃ will also react to produce 0.397 mole of NO.
Finally, we shall determine the mass of 0.397 mole of NO. This can be obtained as follow:
Mole of NO = 0.397 mole
Molar mass of NO = 14 + 16 = 30 g/mol
Mass of NO =?
Mass = mole × molar mass
Mass of NO = 0.397 × 30
Mass of NO = 11.9 g
Thus, the mass of NO produced is 11.9 g
How many atoms would be contained in 454 grams of iron?
Answer:
4.90 x 10 24 atoms
Explanation:
the 24 is the exponent for the 10
2. Two glasses full of water are left out on a table over
night. Both glasses have a diameter of 10
centimeters, but one is twice as tall as the other.
Which glass do you expect to lose more liquid to
evaporation in a short amount of time?
A.The taller glass
B.The shorter glass
C.They both lose the same amount
D.No evaporation takes place
Answer: C
Explanation: The evaporation rate depends on the exposed surface of liquid as long as both glasses stay at the same temperature. Since both glasses have the same surface area, they should both evaporate at the same rate.
=====answer this plss :(
Answer:
Geothermal energy is an uptrending alternative source of production that relies on the earth's crust and elements of radioactivity.
Increase GDP expansion: Philippines could expand their production and hence their industrialization efforts to create a more economies of scales factoring.Produce a cleaner environment: With a cleaner environment with regards to pollution then the citizens can live at a lower mortality rate.2. The reaction of zinc with nitric acid was carried out in a calorimeter. This reaction caused the temperature
of 72.0 grams of liquid water, within the calorimeter, to raise from 25.0°C to 100.°С. Calculate the energy
associated with this reaction.
We want to solve Q = mcΔT for the liquid water; its change in temperature will tell us the amount of thermal energy that flowed out of the reaction. The specific heat, c, of water is 4.184 J/g °C.
Q = (72.0 g)(4.184 J/g °C)(100 °C - 25 °C) = 22593.6 J
Q ≈ 2.26 × 10⁴ J or 22.6 kJ (three significant figures).