Answer:
-A molecule is the smallesr part is compound whereas a compound is the combination of two or more atoms in a fixed proportion by wiehgt.
- A glass of water is an example of compound but a small portion of water can be called molecule.
A sample of 0.562 g of carbon is burned in oxygen in a bomb calorimeter, producing carbon dioxide. Assume both the reactants and products are under standard state conditions, and that the heat released is directly proportional to the enthalpy of combustion of graphite. The temperature of the calorimeter increases from 26.74 °C to 27.93 °C. What is the heat capacity of the calorimeter and its contents?
Answer:
The correct answer is 15.54 kJ per degree C.
Explanation:
The enthalpy change for one mole of a substance, which combines or burns with the oxygen under the standard conditions, that is, at 25 degree C and 1 bar pressure is known as the standard molar enthalpy of combustion. The amount of heat transferred can be calculated by using the formula, q = mcΔT -------------(i)
Here q is the amount of heat transferred, c is the specific heat, ΔT is the change in temperature, and m is the mass of the substance. As in case of bomb calorimeter, mass if considered constant, thus, for calorimeter the equation mentioned will become, q = cΔT ---- (ii)
The standard molar enthalpy of combustion for carbon is -393.5 kJ/mol, that is, -393.5 kJ per mole of heat is generated by burning one mole of carbon. The molecular mass of carbon is 12 gram per mole.
Thus, the number of moles of carbon equivalent to 0.562 grams of carbon can be determined as,
Number of moles of carbon = mass / molecular mas
= 0.562 grams / 12 gram per mole
= 0.047 mol
The heat generated by burning 0.562 grams or 0.047 mole will be,
q = ΔH° × number of moles
= (-393.51 kJ/mol) × 0.047 mol
= -18.49 kJ, the negative sign shows that the heat is produced.
To find heat capacity of calorimeter, put the value of q as -18.49 kJ, for ΔT as (27.93 °C - 26.74 °C) in the equation (ii)
18.49 kJ = c × (27.93 - 26.74)
c = 18.49 kJ/1.19 °C
c = 15.54 kJ/°C
What happens when acetylene reacts with silver powder?
Ravi’s grandmother is suffering from diabetes. Her doctor advised her to take lassi with less fat content. Which of the following methods would be most appropriate for Ravi to prepare it? OPTIONS: a. Filtration b. Decantation c. Churning d. Sedimentation
Answer:
Explanation:
Hello friend
The answer is Churning.
Hope this helps
plz mark as brainliest!!!!!!
When are these words used?
could ,would and should
what's difference between them?
Make 3 sentences using each word
a sentence for 'could': could u pass me the salt?
a sentence for 'would': what would you do if u were the president of usa?
sentence for 'should': you should practise ur spellings before the exam. :)
hope this helps!
why is carbon iv oxide used in fire extinguishers
Answer:
Carbon dioxide extinguishes work by displacing oxygen, or taking away the oxygen element of the fire triangle. The carbon dioxide is also very cold as it comes out of the extinguisher, so it cools the fuel as well.
Apollo 17 astronauts eugene cernan and harrison schmitt collected the last samples of moon rocks to bring back to earth in 1972 The astronauts took measurements of the moon rocks using three categories not affected by gravity this is because the earth and moon have different forces of gravity which measurement did they not use?
A-Volume
B-Weight
C-Mass
D-Density
Answer:
The correct answer is B
Explanation:
This question seeks to test the difference between mass and weight.
Mass is a measurement of the amount of matter present in an object. While weight is a measurement of the force of gravity pulling (the mass of) an object. Hence, measuring the weight of the moon rocks in the moon might be a waste since the weight of the object on earth will produce a different value due to the difference in the force of gravity between the earth and the moon.
Answer:
b
Explanation:
According to periodic trend, which of the following most likely has the highest ionization energy?
Ca
Mn
Br
Zn
Answer:
Br
Explanation:
Ionization energy increases across a period.
All other elements are ahead in the period as compared to Br.
One way of producing drinking water from seawater is by reverse osmosis.
Reverse osmosis is a type of filtration. Seawater is pushed through a semi-permeable membrane. Pressure is applied to the seawater. Semi-permeable
means salt is trapped on one side of the membrane, but water can pass through.
The trapped salts form a ‘seawater concentrate’ on one side of the membrane.
Where do the trapped salts go?
[a] ocean [b]Water distribution system
[c]Storage tank [d]delivery pipeline
QUESTION 3:
Based on the above picture what will determine whether a particle is able to pass
through the membrane?
[a] particle size [b] particle mass
[c] number of particles [d] charge on the particle
the trapped salts go to seawater concentrate
write any two conditions at which a body of certain mass weightless
Answer:
A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity. If the body is falling only under the influence of gravity.
Answer:
A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity.If the body is falling only under the influence of gravity.
What is an empirical formula?
Answer:
a formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.
Hope this helped!!!
Answer:
Empirical formulas show the simplest whole-number ratio of atoms in a compound
Explanation:
how many moles of copper are equivalent to 3.44x10^23 atoms of copper?
Answer:
0.571moles
Explanation:
The Avogrado's number or constant denoted by NA will be used for this question.
The Avogrado's number = 6.022 × 10^23 particles, is contained in 1 mole of a substance.
To get the number of atom/particles in a substance, the formula: N= n × NA is used.
Where; N= Number of atoms in
substance
n= number of moles
NA= Avogadro's constant
Hence, to find the number of moles of copper equivalent to 3.44 × 10^23, we say: n= N / NA
That is, n = 3.44 × 10^23 / 6.022 × 10^23
= 0.5712
Therefore, 0.571 moles of Copper (Cu) is equivalent to 3.44 × 10^23 atoms of Copper.
Please help me...
Atoms of elements X, Y and Z have 16, 17 and 19 electrons, respectively. Atoms of argon have 18 electrons.
a Determine the formulae of the compounds formed by the combination of the atoms of the elements:
(i) X and Z
(ii) Y and Z
(iii) X with itself.
b In each of the cases shown in
A (i)–(iii) above, name the type of chemical bond formed.
c Give two properties you would expect to be shown by the compounds formed in an (ii) and an (iii).
Answer:
a 1) XZ2
2) YZ
3) X2
b 1) Ionic bond
2) Ionic bond
3) covalent bond
c) ionic compounds has high melting and boiling point
ionic compounds can conduct electicity in aqueous form
covalent compounds have electrons shared between the atoms
covalent compounds have lower melting point compared to ionic compound
Answer:
(i) XZ = Potassium Sulfide [K2SO4]
(ii) YZ = Potassium Chloride [KCI]
(iii) X = Sulfur [S]
b) (i) Ionic Bond. (ii) Ionic Bond. (iii) Covalent Bond.
c) (i) Ionic compounds have high melting and boiling points.
(ii) Ionic compounds can conduct electricity in a molten state or a solution as they have ions that can move and carry charge.
(iii) Covalent compounds have low melting and boiling points.
(iv) Covalent compounds can not conduct electricity as all electrons are involved in bonding so there are no free electrons or ions to carry the charge.
Hope this is OK :))
Please mark me as Brainliest:))
In the lab, Amanda has two solutions that contain alcohol and is mixing them with each other. She uses twice as much Solution A as Solution B. Solution A is 11% alcohol and Solution B is 18% alcohol. How many milliliters of Solution B does she use, if the resulting mixture has 320 milliliters of pure alcohol?
Answer:
1,103.47 milliliters
Explanation:
The total percentage of alcohol from solution A and solution B is 29. In a solution that is a mixture of solution A and B, the percentage of alcohol that would be contributed by solution A would be:--
11/29 x 100% = 37.93%
--while the percentage of alcohol that would be contributed by solution B would be:
18/29 x 100 = 62.07%
Hence, if a mixture of A and B has 320 milliliters of alcohol, the amount of alcohol contributed by B would be:
320 x 62.07/100 = 198.624 milliliters
Now, remember that solution B is 18% alcohol. This means that the 18% alcohol content of solution B is 198.624 milliliters. Thus, the total volume of solution B would be:
198.624 x 100/18 = 1,103.47 milliliters.
Therefore, the total milliliters of solution B Amanda used would be 1,103.47.
summer school is over, and I'm feeling self-destructive. Take all of my points and have a good night. 3/3
ayo thanks mate :0000000000000000000000
Express each of the following in standard form.
3.6 x 101
6.452 x 102
8.77 x 10-1
6.4 x 10-3
Answer:3.6 x 101 or 8.77 x 10-1
Which is the correct definition of metallic bonding? Select one: a. an array of positive ions in a sea of electrons b. complete transfer of valence electrons c. atoms share electrons to to be stable
Answer:
I believe it's A) an array of positive ions in a sea of electrons
What is Entropy?
A. The opposite of Enthalpy
B. The temperature at which a reaction is feasible.
C. Free energy used for a reaction.
D. A measure of disorder,
Answer:
D.) A measure of disorder
Explanation:
I got it correct on founders edtell
C12H26 has a what boiling point than C10H22. higher or lower
Determine whether the statement is true or false, and why. "If a theory becomes supported by evidence, it can become a law."
A. False, it should read, "A theory and a hypothesis are already equally supported by evidence, but they have different functions."
B. False, it should read, "If a theory becomes supported by evidence, it can become a hypothesis."
C. True
D. False, it should read, "A theory and a law are already both supported by evidence and are equal, but they have different functions."
Answer: D. False, it should read, "A theory and a law are already both supported by evidence and are equal, but they have different functions."
Explanation:
A "Theory" and a'' Law" in scientific method are already both supported by evidence but they have different function,
The function of " Theory" in scientific method is to give an explanation to the observations and findings gathered during the process. It can be modified, improved or even rejected as more information is being gathered.
While a '' Law '' tends to describe an observed event in nature that is true whenever it is put to test. It does not explain why the occurence or event is true.
Which of the following is not an antioxidant _________
1) Sodium benzoate 2) Sulphur dioxide 3) Sulphite salts 4) Citric acid
Answer: 1. Sodium Benzoate
Explanation: An anti-oxidant is a substance that can help prevent or stop the damage done by free radicals. Examples include; Sulphur Dioxide, Sulphite Salts, Citric Acid, e.t.c
Sodium benzoate is a pure preservative.
Perform the forlowing
mathematical operation, and
report the answer to the correct
number of significant figures.
4568/13 = [?]
Answer:
[tex]\large \boxed{350}[/tex]
Explanation:
In multiplication and division problems, the answer can have no more significant figures than the number with the fewest significant figures.
My calculator gives the result:
[tex]\dfrac{4568}{13} = 351.3846154[/tex]
4658 has four significant figures.
13 has two significant figures.
You must round to two significant figures.
That is, you drop all the digits to the right of the 5 — the red line in Fig. 1 below. You are rounding to the nearest ten.
To round a number to the nearest ten, you look at the number in the ones place (1). See Fig. 2.
If the number to be dropped — the digit in the ones place — is less than 5, you drop the digit in the ones place (Fig. 3). It becomes a zero.
The number in the tens place is a trailing zero. It is not significant.
[tex]\text{The quotient of $\dfrac{4658}{13}$ is $\large \boxed{\mathbf{350}}$}[/tex]
How many primary,secondary and Tertiary carbons are in the compound. 2,3-dimethyl pentane. And
How many primary hydrogen
Answer:
5 primary carbon atoms
3 secondary carbon atoms
4 tertiary carbon atoms
6 hydrogen atoms
Which substance has the highest melting point? Select one: a. sugar b. Oxygen c. Diamond
Answer:
Diamonds
Explanation:
The melting point of sugar is 186C
The melting point of oxygen is -218C
The melting point of diamonds are 4078C
Therefore diamonds have the highest melting point.
You can also think of their structures, as diamonds have a covalent network structure, meaning they are really strong and have a high melting point
Oxygen has a covalent molecular structure
Sugar has a much weaker covalent network structure
Please I need help with this exercise. Does anyone know the solution to it and please with explanations:
Ag(s) + NO3–(aq) + H+(aq) → Ag+(aq) + NO(g) + H2O(l)
When the oxidation-reduction equation above is balanced, what is the coefficient for H+(aq)?
A. 1
B. 2
C. 3
D. 4
Answer:
Option D. 4
Explanation:
Ag(s) + NO3–(aq) + H+(aq) → Ag+(aq) + NO(g) + H2O(l)
To know the coefficient of H+, let us balance the equation. This is can be done as shown below:
Ag(s) + NO3–(aq) + 2H+(aq) → Ag+(aq) + NO(g) + H2O(l)
There are 3 atoms of O on the left side and a total of 2 atoms on the right side. It can be balance by putting 2 in front of H2O as shown below:
Ag(s) + NO3–(aq) + H+(aq) → Ag+(aq) + NO(g) + 2H2O(l)
There are 4 atoms of H on the right side and 1 atom on the left side. It can be balance by putting 4 in front of H+ as shown below:
Ag(s) + NO3–(aq) + 4H+(aq) → Ag+(aq) + NO(g) + 2H2O(l)
Total charge on the left side:
– 1 + 4 = +3
Total charge on the right side:
+1
To balance the charge, we simply put 3 in front of Ag and Ag+ as shown below:
3Ag(s) + NO3–(aq) + 4H+(aq) → 3Ag+(aq) + NO(g) + 2H2O(l)
Now the equation is balanced.
The coefficient of H+ is 4.
Which is the electron configuration for lithium?
1s2
2s3
1s22s1
1s12s2
Answer:
1s2, 2s1
Explanation:
Lithium is the first element in the 2nd row of elements meaning its 1s orbital is completely filled and 1 electron is in the 2s orbital.
Answer:
the answer is C
Explanation:
what is a disavanege for renewable solor power
Mention the uses of a jack serew.
Answer:
ok dear have a nice day
carry on learing
You are pushing a box with 20 N of force that has
a mass of 10 kg, solve for acceleration
Answer:
Force=mass ×acceleration.
20=10×acceleration.
20=10a.
a=2m/s^2.
How can you use the scientific method in everyday life?
You can use the scientific method everyday by asking questions and doing experiments. For example, you want to know how a fire starts, so you do an experiment with it!
Anna is excited about conducting her lab today. She takes out her lab sheet and reads over the lab. She goes and gathers all of the lab materials. She follows each lab procedure step-by-step until she has completed the procedure and recorded all of the data she collected. Afterwards, Anna takes two of the substances and mixes them together to see what would happen. Which lab safety rule did Anna break?
Answer:
Anna didn't wear a lab coat
Explanation:
The first thing anyone who is to carry out a procedure or an experiment in a lab needs to do when he/she enters a lab is to wear a lab coat. This is a lab safety rule that protects the individual from been affected by spillage that could occur as a result of the experiment been conducted.
From the narration in the question, it is not stated anywhere that Anna wore a lab coat before embarking on her lab procedure.
Answer:
C, wear goggles, anytime chemicals, heat, or glassware are used.
Explanation:
This is the correct answer on the Lincoln learning platform.