Answer:
Dependent variable: the children's fear of rabbits
Control: the group that was NOT exposed to loud noises
Independent variable: the loud noises
Experimental Group: the group that was exposed to loud noises
How
many mols are in 151 g of dinitrogen monoxide?
Answer:
3.43 moles
Explanation:
To convert moles into grams you must take the number of grams and divide it by the atomic mass of the compound.
in this case, grams is 151 and N2O has an atomic mass of 44.013
so your equation would look like
151/44.013=3.430804535
your answer would be 3.43 moles
2C10H22 + 3102
20CO2 + 22H2O
What mass of O2 is needed to react completely with 7.5 grams of C10H22?
Answer:
2c11h21
Explanation:
The concentration of H3AsO3 in a solution is determined by titrating it with a 0.1741 M Ce4+ solution. The balanced net ionic equation for the reaction is: 2Ce4+(aq) + H3AsO3(aq) + 5H2O(l) 2Ce3+(aq) + H3AsO4(aq) + 2H3O+(aq) In one experiment, 18.68 mL of the 0.1741-M Ce4+ solution is required to react completely with 30.00 mL of the H3AsO3 solution.
Calculate the concentration of the H3AsO3 solution.
Answer:
0.0542 M
Explanation:
Let;
CA = concentration of Ce4+ solution = 0.1741 M
VA = volume of Ce4+ solution = 18.68 mL
CB = concentration of H3AsO3 = ?
VB = volume of H3AsO3 = 30.00 mL
NA = Number of moles of Ce4+ solution = 2
NB = Number of moles of H3AsO3 = 1
From;
CAVA/CBVB = NA/NB
CAVANB = CBVBNA
CB = CAVANB/VBNA
CB = 0.1741 * 18.68 * 1/30.00 * 2
CB = 0.0542 M
Which ones are soluble in water and which ones are not soluble in water.
a. NH4CH3COO Ammonium acetate soluble
b. Ba(OH)2 Barium hydroxide soluble
c. FeCO3 Iron (II) Carbonate insoluble
d. NaOH Sodium hydroxide soluble
e. RbNO3 Rubidium nitrate soluble
Answer:
d. NaOH Sodium hydroxide soluble
If you picked up a hot coffee mug with lots of thermal energy using your hand, where will the thermal energy transfer to?
Answer:
It will go to your hand.
Explanation: If you touch a hot cup/mug you'll most likely burn yourself, so it would probably go to your hand.
3,01 x 10^23molecules H.O
Answer:
Therefore Mass of 6.022 x10^23 molecules= 32 g.
Explanation:
CsBr formula name???
Answer
PubChem CID/molecular formula
Explanation:
Cesium bromide
PubChem CID 24592
Molecular Formula CsBr or BrCs
Synonyms CESIUM BROMIDE 7787-69-1 Caesium bromide Cesiumbromide Cesium bromide (CsBr) More...
Molecular Weight 212.81 g/mol
Component Compounds CID 260 (Hydrogen bromide) CID 5354618 (Cesium)
have a good day /night
may i please have a branllist
Is liquid ammonia a household acid?
Yes it is an cleaning product
Answer:
yes
Explanation:
it cleans in the house
What is the mass of 3.5 x 10 23 molecules of co2
Answer:
x = 3/6.02 = 0.50.
Explanation:
1 mole of CO2 has 6.02 x 10^23 molecules of CO2.
Say x moles of CO2 has 3.0x10^23 molecules of CO2.
Therefore x = 3/6.02 = 0.50.
True or False: Having a greater volume definitely means a lower concentration (molarity) solution
Having a greater volume definitely means a lower concentration (molarity) of solution. So, the statement is true.
What is meant by molarity of a solution ?Molarity of a solution is defined as the number of moles of solute present per unit volume of solution.
Here,
Since, the number of moles of solute in one litre of solution is known as the molarity, we can say that the change in volume of the solution will affect the molarity of the solution.
Molarity, M = n/V
where n is the number of moles of solute and V is the volume of solution
From the equation, we can say that the molarity of the solution is inversely proportional to its volume.
We know that, molarity of a solution is a temperature dependent parameter.
As the volume of the solution increases, the temperature also increases( Volume [tex]\alpha[/tex] Temperature). When the temperature increases, it affects the molarity of the solution such that the number of moles remains constant and as a result of the increasing volume, the molarity decreases.
Hence,
Having a greater volume definitely means a lower concentration (molarity) of solution.
To learn more about molarity, click:
https://brainly.com/question/29884686
#SPJ2
C. 2.86 g
D. 1.22 g
13. At what Kelvin temperature will 25.2 mol of Xe occupy a volume of 645 L at a pressure of 732 torr?
A. 361 K
B. 291 K
C. 402 K
D. 300 K
charles law . who can please help me with these two problems asap ?
Answer:
k
Explanation:
make a chart to show the effect of Sodium Hydroxide and Sulphuric acid on methyl orange and red litmus paper
Answer:
mark me as brainliest plsss
Hence in the Sodium hydroxide, methyl orange will turn into yellow color and in Sulfuric acid shows red color. Red litmus will turn into blue color in the Sodium hydroxide solution.
What is litmus paper?Litmus paper is a paper which is used to identify the acidity or basicity of any solution.
Sulfuric acid is acidic in nature, and red litmus paper shows no effect in this acid as red paper change into blue in the presence of base. Methyl orange is an indicator and it shows red color in the acidic medium.Sodium hydroxide is basic in nature and red litmus paper will change into blue in this solution and color of methyl orange changes from red to yellow in the basic solution.Hence, the effect of red litmus & methyl orange is explained above.
To know more about litmus paper, visit the below link:
https://brainly.com/question/1287856
The pH of an acidic solution is 5.59. What is [H+]?
Answer:
[H⁺] = 2.57x10⁻⁶ M
Explanation:
This problem can be solved using the definition of pH:
pH = -log[H⁺]
Now we isolate [H⁺] in the equation:
-pH = log[H⁺]
[tex]10^{-pH}[/tex]=[H⁺]
As we are given the pH by the problem, we can now proceed to calculate the [H⁺]:
[H⁺] = [tex]10^{-5.59}[/tex]
[H⁺] = 2.57x10⁻⁶ M
Thus, when the pH of a solution is 5,59; the molar concentration of H⁺ species is 2.57x10⁻⁶.
Where is chemical energy contained in a compound?
A. in the movement of the electrons
B. in the nuclei
C. in the bonds
D. in unbonded electrons
Answer:
C
Explanation:
Energy stored in the bonds of chemical compounds. Chemical energy may be released during a chemical reaction, often in the form of heat; such reactions are called exothermic.
Answer:
The Answer is C.
Explanation:
Cause I'm smart
The sum of the kinetic energy and the potential energy of a particle is its
Answer:
he total mechanical energy E of a particle is defined as the sum of the kinetic and potential energies
Explanation:
Answer:
thermal energy
Explanation:
When the concentration of reactant molecules is increased
Complete question is;
When the concentrations of reactant molecules are increased, the rate of reaction increases. The best explanation for this phenomenon is that as the reactant concentration increases,
A)the average kinetic energy of molecules increases.
B)the frequency of molecular collisions increases.
C)the rate constant increases.
D)the activation energy increases.
E)the order of reaction increases.
Answer:
B) The frequency of molecular collisions increases.
Explanation:
When we increase number of reactant molecules, the effective collision between the reactant molecules will form a product which also increases. As a result, the overall rate of the reaction will also increase which means the frequency of the molecular collision will also increase as well.
Thus, the correct answer is Option B
A 50.0 mL sample of buffer solution contains 0.120 M acetic acid and 0.150 M sodium acetate. If 5.55 mL of 0.092 M NaOH is added to this solution, identify the resulting number of moles of acetic acid, sodium acetate, and NaOH.
Answer:
see calculations below
Explanation:
Given: HOAc ⇄ [H⁺] + [OAc⁻]
C(i) 0.12M 0M 0.15M
mix => 5.55ml(0.092M NaOH) / (50ml + 5.55ml)
= 0.00555(0.092)mole NaOH / 0.0555 L Soln
= 0.0092M in NaOH is added into the initial buffer solution
= 0.0092M in OH⁻ (NaOH is a strong base => 100% ionized)
Rxn => Addition of 0.0092M OH⁻ will react with 0.0092M H⁺ shifting buffer . equilibrium to the right decreasing [HOAc] and increasing [OAc⁻] by . 0.0092M each.
Therfore ...
Given: HOAc ⇄ [H⁺] + [OAc⁻]
C(i) 0.12M 0M 0.15M
ΔC - 0.0092M +x +0.0092M
C(f) 0.1108M x 0.1592M => New Concentrations . after adding 0.0092M . NaOH
Substituting new acid and ion concentrations into Ka expression ...
Ka = [H⁺][OAc⁻]/[HOAc] = (x)(0.1592M)/(0.1108M) = 1.75 x 10⁻⁵M
=> x = [H⁺](new) = (1.75 x 10⁻⁵M*)(0.1108M)/(0.1592M) = 1.22 x 10⁻⁵M in H⁺ ions
*units of Ka are Molar
FYI => Adding a strong base to a buffer solution will shift pH to more basic.
Adding a strong acid to a buffer solution will shift pH to more acidic.
=> (such is a good way to check that your buffer calculations are correct.)
NOTE => Question asks for moles of HOAc, Na⁺OAc⁻ & NaOH after adding base. Giving answers in terms of Molarity (moles/Liter) is same as moles. Therefore ...
[HOAc] = 0.1108M
[NaOAc] = 0.1592M
[NaOH] = ∅M (from rxn of H⁺ + OH⁻ => H₂O, all NaOH was consumed in acid/base reaction. Remaining are only Na⁺ as a spectator ion and OH⁻ as a function of the new concentration of H⁺ => [OH⁻] = Kw/[H⁺] = 1 x 10⁻¹⁴/1.22 x 10⁻⁵ = 8.2 x 10⁻¹⁰M.
Hope this helps. :-)
A chemist fills a reaction vessel with 0.247 M lead(II) (Pb2+) aqueous solution, 0.758 M bromide (Br-) aqueous solution, and 0.109 g lead (II) bromide (PbBr2) solid at a temperature of 20.0 oC. Under these conditions, calculate the reaction free energy deltaG for the following chemical reaction:
Pb2+(aq) + 2Br-(aq) <----> PbBr2(s)
Answer:
ΔG = -24.7kJ/mol
Explanation:
ΔG° of
Pb2+(aq) + 2Br-(aq) ⇄ PbBr2(s)
is:
ΔG° PbBr2 - (2*ΔG°Br- + ΔG°Pb2+)
-261.9kJ/mol - (2*-104.0kJ/mol + -24.4kJ/mol) =
-29.5kJ/mol
ΔG of the reaction is:
ΔG = ΔG° + RT lnQ
Where R is gas constant (8.314x10⁻³kJ/molK)
T is absolute temperature (20°C + 273.15 = 293.15K)
Q is reaction quotient = 1 / [Pb²⁺][Br⁻]²
Replacing:
ΔG = -29.5kJ/mol + 8.314x10⁻³kJ/molK*293.15K ln(1 / [Pb²⁺][Br⁻]²)
ΔG = -29.5kJ/mol + 8.314x10⁻³kJ/molK*293.15K ln(1 / [0.247M][0.758M]²)
ΔG = -24.7kJ/mol
3. Calculate the number of nickel atoms in a 5-cent coin of mass 0.942g if it was made of an alloy consisting of 75% copper and 25% nickel.
please write the equation and help me solve. please no links
Answer: The molality of solution is 1.2 mole/kg
Explanation:
Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.
[tex]Molality=\frac{n}{W_s}[/tex]
where,
n = moles of solute
[tex]W_s[/tex] = weight of solvent in kg
Given : 10 g of glycerol is present in 100 g of solution
moles of glycerol = [tex]\frac{\text {given mass}}{\text {molar mass}}=\frac{10g}{92g/mol}=0.108mol[/tex]
mass of water (solvent )= (100-10) = 90 g = 0.09 kg
Now put all the given values in the formula of molality, we get
[tex]Molality=\frac{0.108mol}{0.09kg}=1.2mole/kg[/tex]
Therefore, the molality of solution is 1.2 mole/kg
Lily is doing a science experiment with a substance in a sealed jar. At first,
the substance's molecules are moving around each other. What will
happen to Lily's substance if she transfers energy into the substance and
causes a phase change? After the phase change, the substance's
molecules will move...'
faster, and the substance will be a liquid.
faster, and the substance will be a gas.
slower, and the substance will be a solid.
slower, and the substance will be a liquid.
Answer:
Faster, and the substance will be a gas.
Explanation:
I'm quite not sure with it. But, I've tried my best. Since maybe the substance is liquid
A potential energy diagram is shown. What is the activation energy of this reaction?
a. 50 kJ
b. 100kJ
c. 150kJ
d. 200kJ
Answer: a. 50 kJ
Explanation: good luck
Which of the following equations correctly describes how to calculate net income? a. net income = (cost of goods sold) - (net sales) - (operating expenses) b. net income = (operating expenses) - (cost of goods sold) - (net sales) c. net income = (operating expenses) + (cost of goods sold) - (net sales) d. net income = (net sales) - (cost of goods sold) - (operating expenses) Please select the best answer from the choices provided A B C D Mark this and return
Answer:
The answer is D. net income= (net sales) - (cost of goods sold)- (operating expenses).
Explanation:
Composition of the air breathed in and the air breathed out changes
Answer:
breathed in air contains oxygen while breathed out air contains higher percentage of CO2
2Fe(s) +3H2SO4(aq) →Fe2(SO4)3(aq) +3H2(g)When 10.3 g of iron are reacted with 14.8 moles of sulfuric acid, what is the percent yield if 5.40 g of "hydrogen gas" are collected?
Answer:
1040%
Explanation:
To solve this question we must convert the mass of Iron to moles in order to find limiting reactant. With limiting reactant we can find the theoretical moles of hydrogen and theoretical mass:
Percent yield = Actual yield (5.40g) / Theoretical yield * 100
Moles Fe -Molar mass: 55.845g/mol-:
10.3g * (1mol / 55.845g) = 0.184 moles of Fe will react.
For a complete reaction of these moles there are necessaries:
0.184 moles Fe* ( 3 mol H2SO4 / 2 mol Fe) = 0.277 moles H2SO4.
As there are 14.8 moles of the acid, Fe is limiting reasctant.
The moles of H2 produced are:
0.184 moles Fe* ( 3 mol H2 / 2 mol Fe) = 0.277 moles H2
The mass is:
0.277 moles H2 * (2.016g/mol) = 0.558g H2
Percent yield is:
5.40g / 0.558g * 100 = 1040%
It is possible the experiment wasn't performed correctly
The gas phase decomposition of nitrogen dioxide at 383 °C
NO2(g)NO(g) + ½ O2(g)
is second order in NO2 with a rate constant of 0.540 M-1 s-1.
If the initial concentration of NO2 is 0.477 M, the concentration of NO2 will be
M after 12.4 seconds have passed.
Answer:
[tex][NO_2]=0.112M[/tex]
Explanation:
Hello there!
In this case, since the second-order integrated law is given by the following equation:
[tex]\frac{1}{[NO_2]} =\frac{1}{[NO_2]_0}+kt[/tex]
Thus, given the initial concentration of the nitrogen dioxide gas, the rate constant and the elapsed time, we obtain:
[tex]\frac{1}{[NO_2]}= \frac{1}{0.477M} +0.54M^{-1}s^{-1}\\\\\frac{1}{[NO_2]}=8.933M^{-1}[/tex]
[tex][NO_2]=\frac{1}{8.933M^{-1}} =0.112M[/tex]
Best regards!
Directions: Read each sentence carefully. Write the letter of the
correct answer on the answer sheet provided.
1. What is produced when two surfaces rub against each other?
A. air
B. pressure
C. motion
D. friction
2. Which surface increases friction?
A. polished B. rough
C. lubricated
D. shiny
3. What causes falling objects to fall?
A. speed
B. gravity
C. acceleration
D. wind
4. Which surface decreases friction?
A. smooth B. rugged
C. rough
D. rocky
5. Why do you move faster when running down a hill?
A. Gravity pulls you up.
C. Gravity pulls you down.
B. Wind pushes you back.
D. Wind pulls you.
Answer:
1 - D) friction
2- B) rough
3- B) gravity
4- A)smooth
5- C)gravity pulls you down
How many grams are in 32.2 L of CO2?
Answer:
63.25 grams of CO₂
Explanation:
To convert from liters to grams, we first need to convert from liters to moles. To do this, we divide the liters by 22.4, the amount of liters of a gas per mole.
32.2 / 22.4
= 1.4375 moles of CO₂
Now we want to convert from moles to grams. To do this, we multiply the moles by the molar mass of CO₂. The total molar mass can be found on the periodic table by adding up the molar mass of carbon (12) and two oxygen (32).
12 + 32 = 44
Now we want to multiply the moles by the molar mass.
1.4375 • 44
= 63.25 grams of CO₂
This is your answer.
Hope this helps!
The melting of ice is considered a/an _______ because the ice absorbs heat from the surroundings.
Question 3 options:
A)
chemical reaction
B)
thermochemical process
C)
exothermic process
D)
endothermic process
Answer:
the correct answer is D
Explanation:
Basically, melting ice is an endothermic reaction because the ice absorbs (heat) energy, which causes a change to occur.