Answer:
the number of electrons
I need help, I just need someone to answer the question today or tomorrow!
Answer:first one is carbon
Explanation:
Other than that I don’t know
In the set up below, which air should show an increase in temperature?
Answer:
My guess is A.
Explanation:
what do molecules and elements have in common
Answer:
They both are made up of atoms and having bonds linking their atoms together.molecules and compounds also share the qualities of being both pure and homogeneous substances.
Explanation:
Hope this helped!!!
Which of these represents a compound ? *
Water
Hydrogen
Oxygen
Answer:
water
Explanation:
H2O
Answer:The answer is water
Explanation: Hydrogen is an element made of an aggregate of hydrogen atoms while oxygen is an element made of oxygen atoms. However, water is a compound made of water molecules.
You are given a stock solution of 500.0 mL of 1.00M magnesium chloride solution. Calculate the volume of the stock solution you would need to use to prepare 250.0 mL of 0.20 M solution.
Answer:
[tex]50\; \rm mL[/tex] of the stock solution would be required.
Explanation:
Assume that a solution of volume [tex]V[/tex] contains a solute with a concentration of [tex]c[/tex]. The quantity [tex]n[/tex] of that solute in this solution would be:
[tex]n = c \cdot V[/tex].
For the solution that needs to be prepared, [tex]c = 0.20\; \rm M = 0.20\; \rm mol \cdot L^{-1}[/tex]. The volume of this solution is [tex]V = 250.0\; \rm mL[/tex]. Calculate the quantity of the solute (magnesium chloride) in the required solution:
[tex]\begin{aligned}n &= c \cdot V \\ &= 0.20\; \rm mol \cdot L^{-1} \times 250.0\; \rm mL \\ &= 0.20\; \rm mol \cdot L^{-1} \times 0.2500\; \rm L \\ &= 0.050\; \rm mol\end{aligned}[/tex].
Rearrange the equation [tex]n = c \cdot V[/tex] to find an expression of volume [tex]V[/tex], given the concentration [tex]c[/tex] and quantity [tex]n[/tex] of the solute:
[tex]\displaystyle V= \frac{n}{c}[/tex].
Concentration of the solute in the stock solution: [tex]c(\text{stock}) = 1.00\; \rm M = 1.00\; \rm mol \cdot L^{-1}[/tex].
Quantity of the solute required: [tex]n = 0.050\; \rm mol[/tex].
Calculate the volume of the stock solution that would contain the required [tex]n = 0.050\; \rm mol[/tex] of the magnesium chloride solute:
[tex]\begin{aligned}& V(\text{stock}) \\ &= \frac{n}{c(\text{stock})} \\ &= \frac{0.050\; \rm mol}{1.00\; \rm mol \cdot L^{-1}} \\ &= 0.050\; \rm L \\ &= 50\; \rm mL\end{aligned}[/tex].
If a young girl learned that it would be 0° C, or 32° F, the next
day then what kind of weather should she expect?
Answer:
Cold
Explanation:
Because 0°C And below or 32°F Refers To Cold Weather
d. 2 5. How many moles of HCl are needed to produce 25 moles of KCl in the presence of excess potassium permanganate? a. 16 b. 32 c. 5 d. 200
Answer:
d. 200.
Explanation:
The reaction is:
2KMnO4 + 16HCl ----> 2KCl + 2MnCl2 + 8H2O + 5Cl2
So 2 moles of KCL are produced form 16 moles of HCL
So 25 moles KCL are made from 25 * (16/2) HCl.
= 25 * 8
= 200 moles. HCl.
On a job application how should you list the schools you attended
Answer:
Usually, you should lay down your educational background by listing the most recent or advanced degree first, working in reverse chronological order. But there are exceptions. Say you earned a degree in geography, but are now working in the field of online marketing. If you more recently completed coursework specific to social media or digital marketing, list that first to grab the reviewer’s attention.
Explanation:
Answer:
Start with the most recent or advanced degree first, working in reverse chronological order.
Explanation:
Which of the following has the highest induced dipole interactions in its molecule?
a. He
b. Ar
c. Ne
d. Kr
Answer:
Option A
Explanation:
In Dipole -induced dipole forces/interactions a polar and a non polar molecule group together to form a bond.
The higher is the electronegativity, the higher is the Dipole-Induce dipole.
As electronegativity defines the ability of an atom to attract a pair of electron in any chemical bond.
The smaller the atom, the higher is the electronegativity and hence the higher is the Dipole -induced dipole forces/interactions
Option A
Life cycles are:
random
divided into two stages
predictable
exactly the same for all species
what is unique about an elements structure?
Explanation:
Atomic Number and MassEach element has its own unique properties. Each contains a different number of protons and neutrons, giving it its own atomic number and mass number. The atomic number of an element is equal to the number of protons that element contains.
Aluminum reacts with chlorine gas to form aluminum chloride according to the reaction below.
2 Al(s)
+
3 Cl2 (g)
2 AlCl3 (s)
How many moles of aluminum chloride can be produced from 2.12 L of chlorine gas at a
temperature of 24 °C and a pressure of 2.27 atm?
Answer:
0.131mol
Explanation:
Firstly, we need to find the number of moles of chlorine gas (Cl2) by using the formula:
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas constant (0.0821 Latm/molK)
T = temperature (K)
Using PV = nRT
n of Chlorine = PV/RT
Based on the information provided in this question, V = 2.12 L, P = 2.27atm, T = 24°C = 24 + 273 = 297K
n = 2.27 × 2.12/ 0.0821 × 297
n = 4.8124/24.3837
n = 0.197
number of moles of Chlorine gas = 0.197mol
The balanced chemical equation provided in this question is as follows;
2 Al(s) + 3Cl2 (g) → 2AlCl3 (s)
3 moles of Cl2 produce 2 moles of AlCl3
0.197moles of Cl2 will produce;
0.197 × 2/3
= 0.394/3
= 0.131mol of AlCl3.
Thermal energy added to a substance that is not changing state causes the substance’s temperature to
Group of answer choices
decrease.
increase
remain unchanged
vary unpredictably
Answer:
increase
Explanation:
Conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction. Conductors include metal, steel, aluminum, copper, frying pan, pot, spoon etc.
In the process of heat conduction, thermal energy is usually transferred from fast moving particles to slow moving particles during the collision of these particles. Also, thermal energy is typically transferred between objects that has different degrees of temperature and materials (particles) that are directly in contact with each other but differ in their ability to accept or give up electrons.
Hence, thermal energy added to a substance that is not changing state causes the substance’s temperature to increase because it would absorb energy in the form of heat.
Find the number of moles in 1.00 x 1023 atoms of chromium.
Answer:
0.17 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
We have
[tex]n = \frac{1.00 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{1}{6.02} \\ = 0.166112[/tex]
We have the final answer as
0.17 molesHope this helps you
Is the formation of CO2(g) from its elements endothermic or exothermic?
Exothermic because the ΔH is negative.
Endothermic because the ΔH is negative.
Endothermic because the ΔH is positive.
Exothermic because the ΔH is positive.
If you traveled 25 meters in 100 seconds, what is your speed?
.25 meters per second
25/100
.25
100/100
1
Michelle learns in science class that simple machines such as an inclined plane can change the amount of force needed to lift heavy objects. She decides to test this with an experiment.
Michelle chooses a 10 kg weight. She sets up a ramp made of smooth metal that makes an angle θ with the floor. She attaches a spring scale to the weight and the top of the ramp in order to hold the weight in place. She records the force from the spring scale, then changes θ and records it again. She repeats this several times.
In this experiment, what is the outcome variable (dependent variable)?
A.
the angle θ between the ramp and the ground
B.
the mass of the weight
C.
the material the ramp is made of
D.
the amount of force on the spring scale
PLEASE I NEED HELP ON THIS RN AND IT'S DUE TODAY!!!!!!!!
IF YOU POST ANY LINKS THAT ARE PERM-BLOCKED, I WILL REPORT YOU, TAKE YOUR POINTS AWAY, DELETE YOUR ANSWER, AND PROBABLY BAN YOU! IF YOU DO NOT KNOW, DON'T ANSWER!!!!!!!
Answer: the amount of force on the spring scale
Explanation:
Molecular geometry of AX2E
Answer:
This molecule is made up of 3 equally spaced sp2 hybrid orbitals arranged at approximately 120o angles. The shape of the orbitals is planar triangular. One orbital contains a lone pair of electrons.
. What is the OH- concentration of a neutral solution?
A neutral solution is one that is neither acidic nor basic. The hydrogen ion concentration equals the hydroxide ion concentration, and both equal 1 X 10-7 M. In a neutral solution, then, pH = pOH = 7.
10 examples of salt in chemistry
Answer:
nacl cacl kcl mgcl k2so4 na2co3 na2so4 kno3 nahco3 naco3
Explanation:
12. Label Each part of the atom:
Answer:
Atom Labeling
Explanation:
Y- neutron
Z-protron
X - electron
W- nucleus
2. Which answer is NOT the definition for one of these terms: volcano,
lava, magma?
O a crack or fracture in the Earth's crust where movement occurs
molten rock stored beneath Earth's surface
magma that erupts on Earth's surface
vents in Earth's crust through which molten rock flows
1.1.2 Differentiate between a micro and macro mineral element,
Explanation:
Macro minerals are present at larger level in the animal body or required in large amount in the diet. Such as calcium, chlorine, magnesium, potassium, sulphur, and sulfur.Micro minerals are often referred to as trace minerals i.e; they are present at low levels in the body and required in smaller amounts in the animal diet. Such as zinc, iron, iodine, cobalt, copper, flurion, etc.Three moles of oxygen gas is stored in a 2.5-liter container at 35°C. What is the pressure of this gas?
Answer:
The pressure of the gas is 30.3072 atm.
Explanation:
An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P * V = n * R * T
In this case:
P= ?V= 2.5 Ln= 3 molesR= 0.082 [tex]\frac{atm*L}{mol*K}[/tex]T= 35 C= 308 K (being 0 C= 273 K)Replacing:
P* 2.5 L= 3 moles* 0.082 [tex]\frac{atm*L}{mol*K}[/tex] *308 K
Solving:
[tex]P=\frac{ 3 moles* 0.082 \frac{atm*L}{mol*K} *308 K}{2.5 L}[/tex]
P= 30.3072 atm
The pressure of the gas is 30.3072 atm.
Question 2 1P Which of the following combinations does not include any state functions? volume, work. temperature, work, pressure, temperature. work, heat
the volume of alcohol present in 409ml of 11%
Answer:
Amount of Alcohol volume present in solution = 44.99 ml
Explanation:
Given:
Total volume of solution = 409 ml
Amount of Alcohol percentage present in solution = 11%
Find:
Amount of Alcohol volume present in solution
Computation:
Amount of Alcohol volume present in solution = Total volume of solution x Amount of Alcohol percentage present in solution
Amount of Alcohol volume present in solution = 409 x 11%
Amount of Alcohol volume present in solution = 409 x 0.11
Amount of Alcohol volume present in solution = 44.99 ml
3. Look at the reaction below:
H2O + C —— CO+ H2
AH = +130kJ mol^-1
Explain what happens to the position of equilibrium if we:
a. increase the pressure
b. increase the concentration of hydrogen gas
c. increase the temperature
d. add a catalyst
Explanation:
a. pressure always favors the side with fewer molecules. in this reaction as both the sides have equal number of molecules, there won't be any change in the position of the equilibrium.
b. when the concentration of the hydrogen gas is increased. more particles would take place in the reaction and so, the rate of reaction would increase favoring the reaction concerning hydrogen gas molecules (backward reaction in this case) therefore, equilibrium would shift to the backward reaction (left).
c. as forward reaction is endothermic, when temperature is increased the equilibrium will shift to the forward reaction (right).
d. catalyst would not have any effect on the position of the equilibrium. it will only increase the rate of reaction.
hope it helps. :)
Which is the reactant - and why?
Explanation:
The substance(s) to the left of the arrow in a chemical equation are called reactants. A reactant is a substance that is present at the start of a chemical reaction. The substance(s) to the right of the arrow are called products . A product is a substance that is present at the end of a chemical reaction
The table shows four solutions that were prepared by
dissolving salt in water.
Solution
Mass of NaCl Volume of Water
(g)
(mL)
A
5.0
50.0
B
5.0
75.0
С
5.0
100.0
D
5.0
125.0
Which of the solutions has the highest salt
concentration?
O A. Solution B
OB. Solution D
O C. Solution C
O D. Solution A
Answer:
a
Explanation:
The solution that has the highest concentration given the data is solution A ( Option D)
What is molarity?This is defined as the mole of solute per unit litre of solution. Mathematically, it can be expressed as:
Molarity = mole / Volume
How to determine the mole of NaCl Mass of solute = 5 g Molar mass of NaCl = 58.5 g/mol Mole of NaCl =?Mole = mass / molar mass
Mole of NaCl = 5 / 58.5
Mole of NaCl = 0.085 mole
How to determine the molarity of solution AMole of NaCl = 0.085 mole Volume = 50 mL = 50 / 1000 = 0.05 L Molarity of solution A =?Molarity = mole / Volume
Molarity of solution A = 0.085 / 0.05
Molarity of solution A = 1.7 M
How to determine the molarity of solution BMole of NaCl = 0.085 mole Volume = 75 mL = 75 / 1000 = 0.075 L Molarity of solution B =?Molarity = mole / Volume
Molarity of solution B = 0.085 / 0.075
Molarity of solution B = 1.13 M
How to determine the molarity of solution CMole of NaCl = 0.085 mole Volume = 100 mL = 100 / 1000 = 0.1 L Molarity of solution C =?Molarity = mole / Volume
Molarity of solution C = 0.085 / 0.1
Molarity of solution C = 0.85 M
How to determine the molarity of solution DMole of NaCl = 0.085 mole Volume = 125 mL = 125 / 1000 = 0.125 L Molarity of solution D =?Molarity = mole / Volume
Molarity of solution D = 0.085 / 0.125
Molarity of solution D = 0.68 M
SUMMARY
Molarity of solution A = 1.7 MMolarity of solution B = 1.13 MMolarity of solution C = 0.85 MMolarity of solution D = 0.68 MThus, solution A has the highest concentration of the salt.
Learn more about molarity:
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2) What is the mass of a sample that produces -1,500 J if the specific heat is 1.0 and the temperature decreases by 30℃?
3) What is the specific heat (C) of silver if we heat a 16g cube from 45 oC to 80 oC and it absorbs 41.3 J of thermal energy?
Answer:
(2) 50 kg
(3) 73.75 J/kg.K
Explanation:
(2) From the question,
Using,
q = mcΔt........................ Equation 1
Where q = amount of heat, m = mass. c = specific heat capacity, Δt = change in temperature
make m the subject of the equation
m = q/(cΔt)..................... Equation 2
Given: q = 1.500 J, c = 1.0 J/kg.K, Δt = 30°C
substitute these values into equation 2
m = 1500/(1×30)
m = 50 kg
(3) using
q = cm(t₂-t₁).
Where t₁ and t₂ = initial and final temperature respectively
making c the subject
c = q/m(t₂-t₁)................ Equation 3
Given: q = 41.3 J, m = 16 g = 0.016 kg, t₂ = 80°C, t₁ = 45°C
Substitute these values into equation 3
c = 41.3/0.016(80-45)
c = 41.3/0.56
c = 73.75 J/kg.K