Answer:
its very dark and scary
Explanation:
Which term is used to measure a star's brightness?
Answer:
Magnitude
Explanation:
Astronomers define star brightness in terms of magnitude (how bright the star appears from Earth)
Can some answer this?
It is the gametes formation of a sex cells or reproductive cells.
Answer:
Meiosis
Explanation:
.bnsksksksjabsn...
Answer:
sana makatulong po sainyo
Why can’t neon store energy in this way?
Answer:
Neon is a noble gas, it is monoatomic in nature, which implies that it has only one atom present. If we compare neon with water, water has three atoms present, two hydrogen atoms and one oxygen atom. Hence water stores more energy than neon because it is polyatomic and contains chemical bonds.
Select the correct answer.
What does the empirical formula of a compound describe?
Ο Α. .
the type and number of atoms
OB.
the type and ratio of atoms
O C.
the number of atoms
OD
the type and mass of atoms
Reset
Next
Answer:
b
Explanation:
cause empirical formular is the elementary or the foundation for molecular formula and molecular formula depends on the empirical formula
another name for constant boiling mixture
Answer:
Azeotrope
Explanation:
An azeotrope is a liquid mixture that has a constant boiling point and whose vapor has the same composition as the liquid
Another name for constant boiling mixture.
[tex]\sf\purple{Azeotrope.}[/tex] ✅
An azeotrope or a constant boiling point mixture is a mixture that has the same composition in liquid and vapour phase.[tex]\large\mathfrak{{\pmb{\underline{\orange{Happy\:learning }}{\orange{!}}}}}[/tex]
Which has more molecules in it 10g H, 0 or 10g NaCl*
A)010g of H0
B)10g of NaCl
C)They have the same number of molecules
D)Cannot be determined
Answer:
10 grams of hydrogen
Explanation:
I. Witch direction does the electric field point at a position directly west of a positive charge
Answer:
The answer is North
Explanation:
The direction of the field is taken to be the direction of the force it would exert on a positive test charge.
If the pH of a solution is 3, its pOH is
Explanation:
If the pH of a solution is 3, its pOH is 14-3= 11
mention two examples each of solid liquid and gaseous Alkanes
Answer:
gas ; methane , ethane
liquid ; octane , hexane
Explanation;
i cant find solid dear
pls help anyone with an example of a solid alkanes
Which of these is true for natural selection but not artificial selection?
A.Humans choose specific organisms to reproduce.
B.Competition for resources determines reproductive success.
C.Unfavorable traits decrease in frequency in a population.
D.Genetic engineering introduces new traits into a population.
Answer:
B
Explanation:
Determine the mass of the following samples.
7.52 X 10 25molecules of NH3
Explanation:
Find moles first
moles = number of particles/ 6×10^23
= 7.52 ×10^25 / 6×10^23
=125.33
calculate molar mass
(1×14) +(3×1) =17
convert to mass
mass= moles × molar mass
=125.33 × 17
=2130.67g
This is a pretty big value usually it's smaller but I'd assume it's because the number of particles was large.
A chemist has three different acid solutions. The first acid solution contains 15 % 15% acid, the second contains 35 % 35% and the third contains 80 % 80% . They want to use all three solutions to obtain a mixture of 190 190 liters containing 30 % 30% acid, using 2 2 times as much of the 80 % 80% solution as the 35 % 35% solution. How many liters of each solution should be used
Answer:
First solution = 133L
Second solution = 19L
Third solution = 38L
Explanation:
As we want to make 190L of a 30%=0.3 solution we can write:
190L*0.3 = a*0.15 + b*0.35 + c*0.80
Where a, b and c are the volume of first, second and third acid solutions, respectively.
The volume of c is twice volume of b:
c = 2b
And the volume of the 3 solutions is equal to 190L:
190L = a+b+c
190L = a+3b
190L*0.3 = (190-3b)*0.15 + b*0.35 + 2b*0.80
57 = 28.5-0.45b+0.35b+1.6b
28.5 = 1.5b
b = 19L
c = 2*19L
c = 38L
a = 190L - 19L - 38L
a = 133L
How many liters of hydrogen gas will be produced at STP from the reaction of 5.159 x 1021 atoms of magnesium with 55.23 g of phosphoric acid (H3PO4)?
3 Mg + 2 H3(PO4) Mg3(PO4)2 + 3 H2
Answer:
0.190L of hydrogen may be produced by the reaction.
Explanation:
Our reaction is:
3Mg + 2H₃PO₄ → Mg₃(PO₄)₂ + 3H₂
We need to determine the limting reactant. Let's find out the moles of each:
5.159×10²¹ atoms . 1 mol / 6.02×10²³ atoms = 0.00857 moles of Mg
55.23 g . 1 mol / 97.97 g = 0.563 moles of acid
2 moles of acid react to 3 moles of Mg
0.563 moles of acid may react to: (0.563 . 3) /2 = 0.8445 moles of Mg
Definetely the limting reactant is Mg.
As ratio is 3:3, 3 moles of Mg can produce 3 moles of hydrogen
Then, 0.00857 moles of Mg must produce 0.00857 moles of H₂
At STP, 1 mol of any gas occupies 22.4L
0.00857 mol . 22.4L / 1mol = 0.190L
How many moles are in 4.01x10^24 particles?
Answer:
6.64
Explanation:
so moles
[tex] \frac{number \: of \: \: particles \: }{6.02 \times {10}^{23} } [/tex]
then do =4.01×10^24/6.02×10^23
you get the answer as 6.6445 u only need to write the answer to
3.S.F 6.64 moles
hope this make sense :)
If crystal growth does not start on its own after the solution in the flask returns to room temperature, identify the best ways to promote this process. Select one or more: Add a bit of solid as a seed crystal. Scratch the bottom of the flask gently with a stirring rod. Place the flask on a hot plate to evaporate some solvent. Add ice cubes to the solution.
Answer: The best way to promote the process are:
--> Add a bit of solid as a seed crystal.
--> Scratch the bottom of the flask gently with a stirring rod.
Explanation:
A crystal growth is seen is SUPERSATURATED solutions which contains more solute than it can normally dissolve at that given temperature. It is usually very UNSTABLE and capable of releasing the excess solute if disturbed, either by shaking or seeding with a tiny crystals.
Crystallization can be used for the separation of two salts with different solubilities as well as for purification of a soluble salt that contains insoluble solid impurities. Recrystallization improves the validity of the process. Crystallization can be initiated by:
--> Scratching the bottom of the flask gently with a stirring rod: scratching initiates crystallization by providing energy from the high-frequency vibrations.
--> Adding a bit of solid as a seed crystal: Seed crystals create a nucleation site where crystals can begin growth.
The word habitable is defined as:
How many centimeters are in 5 miles? Hint: 1 miles = 5280 feet
How many grams of silver nitrate will be needed to produce 8.6 g of silver?
Answer:
13.5g of AgNO3 will be needed
Explanation:
Silver nitrate, AgNO3 contains 1 mole of silver, Ag, per mole of nitrate. To solve this problem we need to convert the mass of Ag to moles. Thee moles = Moles of AgNO3 we need. With the molar mass of AgNO3 we can find the needed mass:
Moles Ag-Molar mass: 107.8682g/mol-
8.6g * (1mol / 107.8682g) = 0.0797 moles Ag = Moles AgNO3
Mass AgNO3 -Molar mass: 169.87g/mol-
0.0797 moles Ag * (169.87g/mol) =
13.5g of AgNO3 will be neededA solution in which the [H+] is 1.0 X 10-4 mol/L is said to be:
how a forensic scientist may match DNA of evidence to a particular crime?
the element magnesium has 3 orbital and 3 electrons true or false
Answer: True
Explanation:
Use the reaction N2(g) + 3H2(g) 2NH3(g) to answer the following questions
a. 1 pt: What does Le Châtelier's principle predict would happen to the equilibrium conditions if N2(g) + 3H2(g) were added to the system?
b. 1 pt: What would happen to the equilibrium if the pressure were decreased?
c. 2 pts: Write the equation for calculating Keq
d. 3 pts: Calculate the value for Keq given the following concentrations
[NH3] = 6 M
[H2] = 4 M
[N2] = 3 M
Answer:
K
C
=
[N
2
][H
2
]
3
[NH
3
]
2
N
2
+3H
2
⇌2NH
3
=
(1.5×10
−2
)(3×10
−2
)
3
(1.2×10
−2
)
2
=
1.5×10
−2
×27×10
−6
1.44×10
−4
=
40.5×10
−4
1.44
=0.035×10
4
What is the simplest whole number ratio of atoms in a molecule or formula unit called?
the molecular formula
the molar mano
the percent composition
the empirical formula
PLEASE HELPP
The compounds that form from the bonding of the hydroxyl group (-OH) to a hydrocarbon are called the aldehydes.
True
False
Answer:
False.
I just got it right, lol.
How many atoms are in 0.432 g of KNO3? Round your answer to three significant
figures.
A…2.58 x 1021
B…7.10 x 10-27
C…0.00428
D…43.6
A
I did it and got this but it know the first one is right as it only missing of some point it will be calculator error and also the answer is to the power of 21.
hope this make sense :)
How many milliliters of 5.0 M NaOH are needed to exactly neutralize 40. milliliters of 2.0 M HCl?
Answer:
16mL
Explanation:
Using the following formula;
CaVa = CbVb
Where;
Where
Ca = concentration/molarity of acid (M)
Va = volume of acid (mL)
Cb = concentration/molarity of base (M)
Vb = volume of base (mL)
According to the information provided in this question;
Ca (HCl) = 2M
Cb (NaOH) = 5M
Va (HCl) = 40mL
Vb (NaOH) = ?
Using CaVa = CbVb
Vb = CaVa/Cb
Vb = 2 × 40/5
Vb = 80/5
Vb = 16mL
how many moles are in 150 grams of water
Answer:
Solution given:
H20=1+1+16=18grams
we have
1 mole of water =18grams
now
150grams of water=1/18*150=25/3 =8.33mole.
150 grams of water =8.33mole.
Note:
mole =given mass/actual mass of molecule/atom
1 mole of water is 18 grams.
Then,
150 grams of water,
→ 1/18 × 150
→ 25/3
→ 8.33333 . . .
Hence, 150 grams of water is 8.3 moles.
what form of the ideal gas law would you use to calculate the volume of gas
Answer:
V = nRT/P
Explanation:
The ideal gas law states that
PV=nRT
where P = pressure, V = volume, n = number of moles, R = ideal gas constant, and T= temperature
P V = n R T
to get V on its own, divide both sides of the equation by P
V = (nRT)/P
Given the reaction:
Ca + 2H,0→ Ca(OH)) + H2
How many moles of H,O are needed to exactly react with
2.0 moles of Ca
Answer:
4
Explanation:
because use the molar ratio of
ca:h2o
1:2
2;4
so u times it by 2 .
hope this helps:)