If a piece of pure gold jewelers weighs 11.81 grams, how many atoms is it made of?
Answer:30.573 Billion atoms are in one gram
Explanation:
CAN SOMEONE PLEASE HELP ME WITH THIS I REALLY NEED HELP
Answer:
B
Explanation:
There's a three in front of the CH3COOH. But let's figure it out without that 3.
1 mol of CH3COOH has 3 H from CH3 and 1 hydrogen at the end. In all 4 hydrogens.
Now put the 3 in front 3CH3COOH multiplies everything by 3. So you had 4 before and with the 3 in front you must have 12.
Try it. Draw it out.
CH3COOH has 4
CH3COOH has 4
CH3COOH has 4
Total 12
That's B
Phenolphthalein meaning
Answer:
Phenolphthalein is a chemical compound with the formula C20H14O4 and is often written as "HIn" or "phph" in shorthand notation. Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions.
Answer:
Phenolphthalein is a chemical compound, a colorless crystalline solid, though pink in a alkaline solution, and is also used as an acid-base indicator.
Explanation:
Use the equation below:
2Na + Cl2 ==> 2NaCl
+ O
How many grams of NaCl are produced when 1.25 moles of Cl2 reacts with Na?
Explanation:
2/1×1.25
=2.5 mole of NaCl are produced
weight of NaCl produced = moles × molar mass of NaCl
weight of NaCl produced = 2.5×58.5
weight of NaCl produced =146.5 grams
How many formula units are there in 14.50 moles of any compound?
___X 10^___formula units
Answer:
8.73 × 10²⁴ formula units
Explanation:
To calculate the number of formula units a substance contain, we multiply the number of moles by Avagadro number (6.02 × 10²³)
number of formula units = 14.50 moles × 6.02 × 10²³
= 87.29 × 10²³
= 8.73 × 10²⁴ formula units.
Which of the following is a correct statement about water? (3 points)
Hydrogen bonding causes water to be strongly cohesive.
Hydrogen bonding causes water to have a low surface tension.
Water is a universal solvent because polar and nonpolar solutes can dissolve in it.
Water is less dense as a liquid than as a solid because of changes in bond structure.
Answer:
A: Hydrogen bonding causes water to be strongly cohesive.
Explanation:
Water has a high surafce tension. Hence droplets of water
Water cannot dissolve non polar substances like oil; only polar
Water is actually less dense in solid form :)
Hydrogen bonding causes water to be strongly cohesive.
This sticking together of like substances is called cohesion. Depending on how attracted molecules of the same substance are to one another, the substance will be more or less cohesive. Hydrogen bonds cause water to be exceptionally attracted to each other. Therefore, water is very cohesive.
Cohesion
Cohesion, also called cohesive attraction or cohesive force, is the action or property of like molecules sticking together, being mutually attractive. It is an intrinsic property of a substance that is caused by the shape and structure of its molecules, which makes the distribution of surrounding electrons irregular when molecules get close to one another, creating an electrical attraction that can maintain a microscopic structure such as a water drop. In other words, cohesion allows for surface tension, creating a "solid-like" state upon which light-weight or low-density materials can be placed.
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The movement of water from an area of high concentration to one of low concentration through a semipermeable membrane is called ?
How many moles of aluminum sulfide will be produced if 12 moles of Sg react?
Answer:
Molar mass = [9(12.0)+8(1.01)+4(16.0)] = 180.1 g/mol Moles = 112 g 1 mol x 180.1 g = 0.622 mol (3 sig figs)
Explanation:
Which equation correctly represents the dissociation of a strong acid in water?
Question 26 options:
CH3COOH ↔H++ CH3COO−
NaOH →Na++OH−
HCl →H+ +Cl−
NH3+ H2O↔ NH4++ OH−
The equation that correctly represents the dissociation of a strong acid in water is as follows: HCl → H+ + Cl−
What is acid dissociation?Acid dissociation is the process by which an acid breaks up into it's constituent ions in an aqueous solution.
Acids are known to contain hydrogen ions (H+), hence, dissociate into H+ and an anion.
A strong acid like HCl dissociates completely in an aqueous solution while a weak acid does not dissociate completely.
According to this question, hydrogen chloride (HCl) is said to dissociate into hydrogen ion (H+) and chloride (Cl-) according to the following expression:
HCl → H+ + Cl−
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Carbon dioxide and water are produced when pentane (C5H12) reacts with oxygen. What is the balanced equation for this reaction?
○C5H12(g) + O29) - CO2(g) + H2O(g) ○C5H12(g) + O2(g) - 5CO2(g) + H2O(g)
○C5H12(g) +802(g) - 5CO2(g) + 6H2O(g) ○5CO2(g) + 6H2009) - C5H12(g) + 802(g)
○C5H12(g) +502(g) - 5CO2(g) + 6H2(g)
○CH2(g) +O2(g) + CO2(g) + H2(g)
Answer:
C
Explanation:
C5H12(g) +802(g) - 5CO2(g) + 6H2O(g)
The balanced chemical equation of pentane (C5H12) which reacts with oxygen is
C5H12(g) +802(g) - 5CO2(g) + 6H2O(g)
What is balanced chemical equation?It is the chemical equation in which the atom or molecules or moles of elements on both side reactant and product.
Our reactants are pentane and oxygen. Since, fourth and sixth reaction do not contain pentane. Therefore, fourth and sixth reaction are wrong.
Now, our next step is to compare product.
As we know that, Carbon dioxide and water are produced when pentane (C5H12) reacts with oxygen. So, we get to the conclusion that carbon dioxide and water are the product.
Since, rest of the equation have carbon dioxide and water as product.
On reactant side, there are 5 carbon atoms and 12 hydrogen atom. So, on product side there must be 5 carbon atoms and 12 hydrogen atom. Now we balance the oxygen atom on both side.
Thus, we concluded that the balanced chemical equation of pentane (C5H12) which reacts with oxygen is
C5H12(g) +802(g) - 5CO2(g) + 6H2O(g).
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Tritium (hydrogen-3) has a half-life of 12.3 years. How old is a bottle of wine if the tritium content is determined to be 25% in new bottle of wine
Answer:
24.6 years
Explanation:
Applying,
A = (A')[tex]2^{a/n}[/tex]..................... Equation 1
Where A = Original Tritium content in the wine, A' = Tritium content in the wine after decay, a = age of the old bottle, n = half life of Tritium
From the question,
Let A = X, therefore, A' = 0.25X
Given: n = 12.3 years
Substitute these values into equation 1
X = 0.25X([tex]2^{a/n}[/tex])
1 = 0.25×([tex]2^{a/12.3}[/tex])
1/0.25 =
4 = [tex]2^{a/12.3}[/tex]
[tex]2^{a/12.3}[/tex] = 2²
Equation the base,
a/12.3 = 2
a = 12.3×2
a = 24.6 years
Explain the method to decrease friction?
Answer:
having a smooth or lubricated surface may help decrease friction.
Explanation:
Teresa has taken three tests worth 100 points each. Her scores are 85, 93, and 88. She has one test left to take.
To get an average score of 90, what must the sum of all her test scores be?
a.
400
c.
600
b.
360
d.
300
Answer:
SOrry it makes me writer sotufjksankdn
Explanation:
I’d appreciate the help! :)
Here is the reaction:
3 NO2 (g) + H2O (l) = 2HNO3 (l) + NO (g)
Answer: 300g
Explanation:
first we write the given values on top
224L. x
3 NO2 (g) + H2O (l) = 2HNO3 (l) + NO (g)
22.4L 30g
then we form a formula
224L/22.4L= x/30g
224*30/22.4
6720/22.4= 300g
What is the pH of a solution with an H3O+ concentration of 5.67 x 10-4 M?
a. 1.00
b. 3.25
C. -1.00
d. -3.25
Answer:
3.25Explanation:
The pH of a solution can be found by using the formula
[tex]pH = - log [ { H_3O}^{+}][/tex]
From the question we have
[tex]ph = - log(5.67 \times {10}^{ - 4} ) \\ = 3.2464[/tex]
We have the final answer as
3.25Hope this helps you
Balance the following equation: _H2+ __02 - __ H20
Answer:
2
H
2
+
O
2
=
2
H
2
O
Explanation:
From the original equation, you first need to write each component separately.
H
2
+
O
2
=
H
2
O
Left side: H = 2 ; O = 2 (number based on the subscript)
Right side: H = 2 ; O = 1 (number based on the subscripts; no subscript means that the element is just 1)
Notice that the number of H is already balance but the number of O is not. In order to balance the O, you need to multiply the element by 2, but you CANNOT do this by simply changing the subscript.
Hence,
H
2
+
O
2
=
2
H
2
O
Left side: H = 2 ; O = 2
Right side: H = 2 x 2 = 4 ; O = 1 x 2 = 2
Now, notice that the number of O is now balance (both are 2) but the number of H is not (since
H
2
O
is a substance and not an element, you need to multiply everything by 2). So, what to do?
You also multiply the left side H by 2. Hence,
2
H
2
+
O
2
=
2
H
2
O
Left side: H = 2 x 2 = 4 ; O = 2
Right side: H = 2 x 2 = 4 ; O = 1 x 2 = 2
The equation is now balanced.
Balance the following equation:
Cr + __02 +_Cr203
Answer:
4Cr + __302 -->_2Cr203.....
2Al + 6HCl --> 2AlCl3 + 3H2 Aluminium reacts with hydrochloric acid. How many grams of aluminum are necessary to produce 11 L of hydrogen gas at STP? ( 8.8 g )
Answer:
8.8g of Al are necessaries
Explanation:
Based on the reaction, 2 moles of Al are required to produce 3 moles of hydrogen gas.
To solve this question we must find the moles of H2 in 11L at STP using PV = nRT. With these moles we can find the moles of Al required and its mass as follows:
Moles H2:
PV = nRT; PV/RT = n
Where P is pressure = 1atm at STP; V is volume = 11L; R is gas constant = 0.082atmL/molK and T is absolute temperature = 273.15K at STP
Replacing:
1atm*11L/0.082atmL/molK*273.15K = n
n = 0.491 moles of H2 must be produced
Moles Al:
0.491 moles of H2 * (2mol Al / 3mol H2) = 0.327moles of Al are required
Mass Al -Molar mass: 26.98g/mol-:
0.327moles of Al * (26.98g / mol) = 8.8g of Al are necessaries
0.444 mol C2H5OH= how many molecules
Explanation:
hope it make sense to u :)
How many ml of a 6.00M HNO would be required to prepare 200ml of a 2.50M
solution?
83.33ml
72.98ml
86.23ml
64.98ml
Answer:
83.33ml
Explanation:
Firstly, let's notice that 200ml are equal to 0.2L
M=number of moles of the solute ÷ number of liters. Let's call the number of liter by x:
2.5=x÷0.2
x=2.5×0.2
x=0.5
It means you'll need 0.5 mol of HNO. But your solution have 6 moles per liter, so how much do you need? Divide the moles by 12 to have 0.5, so now you need to divide the liter per 12 too. The liter is equal to 1000ml, so:
1000ml÷12=83.33ml
A gas has an initial pressure of 120 kPa, a volume of 23 liters, and a temperature of 20°C. If the pressure is raised to 150 kPa the new volume is 17 liters, what is the new temperature of the gas? *
A.100 K
B.0.003 K
C.270.7 K
D.18.4 K
Does heat flow out of the atmosphere (HQ)
change during the day?
Answer:
The heat flow into Earth's atmosphere varies as the Sun rises and sets, gradually increasing during the day and falling to zero at night.
Explanation:
Heat radiates from the ground into the lower atmosphere. In conduction, heat moves from areas of more heat to areas of less heat by direct contact. Warmer molecules vibrate rapidly and collide with other nearby molecules, transferring their energy.
Study the particle below carefully and answer
the questions that followed.
a)ldentify the particle.
b)Write the electronic configuration of the
particle.
c)State
i.Atomic number
ii.Mass number
iii.Proton number
iv.Electron number
d) Calculate the neutron number
e) State the valency
f)What is the valence electrons?
Answer:
b is the answer hope that helps
2Cr^3 + 3Zn(s) -> 2Cr(s) + 3Zn^2 + (aq) which reactant is reduced and which is oxidicided
Answer:
Cr is oxidised
and
Zn is reduced
[ Reduced reactant ] :
Cr^( + 3 ) + 3 e^( - 1 ) ===》 Cr^( 0 )
_____________________________
[ Oxidicided reactant ] :
Zn^(0) ===》Zn^( + 2 ) + 2 e^( - 1 )
PLEASE QUICKLY. I'll give BRAINLIEST. A sample contains 25% parent isotope and 75% daughter isotopes. If the half-life of the parent isotope is 72 years, how old is the sample?
144 years old
216 years old
288 years old
360 years old
From the calculations and the principles of radioactivity, the age of the parent isotope is 144 years
What is radioactivity?The term radioactivity has to do with the spontaneous decay of a substance.
We know that we have about 25% parent isotope still remaining hence;
[tex]0.693/t1/2 =2.303/t log No/N\\When N =0.25 No and t1/2 = 72 years\\0.693/72 =2.303/t log No/0.25No\\0.0096 = 2.303/t *0.60206\\0.0096 = 1.3865/t\\t = 1.3865/0.0096\\t =144 years[/tex]
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Answer:
A. 144 years old
Explanation:
Does the excess reactant get used up completely in a reaction??
Answer:
In a chemical reaction, reactants that are not used up when the reaction is finished are called excess reagents. The reagent that is completely used up or reacted is called the limiting reagent, because its quantity limits the amount of products formed.
Explanation:
What element is produced when Mercury - 204 undergoes alpha decay?
Answer:
bismuth
Explanation:
i think if not i am so sorry
2. How did the Activator affect the mixture?
Answer:
Activator effects a mixture if you put to much of the activator your using into a product or thing you are using.
Explanation:
For ex.
If you poor to much activator into slime it will make the slime hard and very wet it will ruin your slime completely so you will have to do it just right but start off pouring it slowly and mix and then more if it needs more.
Sodium chloride is produced from its elements through a synthesis reaction. What mass of each reactant would be required to produce 22.0 mol of sodium chloride? sodium
Answer:
506.0 g sodium and 778.8 g chlorine gas
Explanation:
The elements from which sodium chloride (NaCl) is composed are sodium (Na) and chlorine (Cl). Thus, the chemical equation for the production of sodium chloride (NaCl) from sodium (Na) and chlorine gas (Cl₂) is the following:
2Na(s) + Cl₂(g) → 2NaCl(s)
According to the balanced equation, 2 moles of NaCl are produced from 2 moles of Na(s) and 1 mol of Cl₂. To produce 22.0 mol of NaCl, we need:
22.0 mol NaCl x 2 mol Na(s)/2 mol NaCl = 22.0 mol Na(s)
22.0 mol NaCl x 1 mol Cl₂/2 mol NaCl = 11.0 mol Cl₂
Now, we convert the moles of each reactant to grams with the molar mass (MM) of the compound:
MM(Na) = 23 g/mol
22.0 mol Na x 23 g/mol = 506.0 g Na(s)
MM(Cl₂) = 35.4 g/mol x 2 = 70.8 g/mol
11.0 mol Cl₂ x 70.8 g/mol = 778.8 g Cl₂
Therefore, it is required a mass of 506.0 grams of Na(s) and a mass of 778.8 grams of Cl₂ to produce 22.0 mol of NaCl.
why metal in the middle of metal activity series can't be obtained by heating ors in air
Answer:
See Explanation
Explanation:
The way by which a metal is obtained from its ore is determined by the chemical reactivity of the metal.
Metals that are highly reactive are chiefly obtained by electrolysis of the metal salt. These metals are found high up in the metal activity series.
Metals that are at the middle of the series are moderately reactive and are obtained by electrolysis or by reduction since they still form ionic salts.
Metals that are far lower in the series can only be obtained by heating them in air because they are mostly unreactive.
Hence, moderately reactive metals at the middle of the series are not obtained by roasting in air.