Answer:
Mass = 2.16 g
Explanation:
Given data:
Number of molecules of F₂ = 3.45 × 10²²
Mass in gram = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
3.45 × 10²² molecules ×1 mol / 6.022 × 10²³ molecules
0.57× 10⁻¹ mol
0.057 mol
Mass in gram :
Mass = number of moles × molar mass
Mass = 0.057 mol × 37.9 g/mol
Mass = 2.16 g
17 Which changes decrease the rate of reaction between magnesium and air?
1.heating the magnesium to a higher temperature
2.using a higher proportion of oxygen in the air
3.using magnesium ribbon instead of powdered magnesium
A 1, 2 and 3
B 1 only
C 2 only
D 3 only
Using magnesium ribbon instead of powdered magnesium decrease the rate of reaction between magnesium and air.
What is rate of reaction?Rate of reaction tells about the duration of the completion of the reaction.
Rate of any reaction is directly proportional to the concentration and surface area of the reactant, temperature, catalyst, no. of collision, activation energy, etc.
So, if we magnesium in the ribbon instead of powdered magnesium the surface area of the reactant side decreases which results in the decrease of the rate of reaction.
Hence, option (D) is correct i.e. rate of reaction decreases on using magnesium ribbon instead of powdered magnesium.
To know more about rate of reaction, visit the below link:
https://brainly.com/question/1898560
1. a metal with 3 valence electrons, used in cans.
2. a period 3 element that will not react naturally.
3. has 5 valence electrons and in period 3.
4. the most reactive metal.
Answer:
.
Explanation:
1. aluminum
2. argon
3. phosphorus
4. francium
I cant really explain this one
please one more last help me on my task to go on baby corp
Answer:?
Explanation: i'm confused with this and i know i should be writing this in comments but if you can explain me the question maybe i could help you
Zuzana tests a common household substance and finds that it has a pH of 3.
What type of substance is in the scenario?
acidic
basic
salt
neutral
pH is a measurement of amount of hydronium ion H₃O⁺ in a given sample. More the value of hydronium ion concentration, more will be the solution acidic. The given substance is acidic. The correct option is option A.
What are acid and base?Acid is a solution which releases H⁺ hydrogen ion when dissolved in water. Base are the solution which releases hydroxide ion OH⁻ ion when dissolved in water. The pH of acid is between 0-7 on pH scale while for base pH range is from 7-14.
On subtracting pH from 14, we get pOH which measures the concentration of hydroxide ion in a given solution. pH depend on the temperature. At room temperature pH scale is between 0 to 14. pH of neutral solution is 7.
Therefore, the given substance is acidic. The correct option is option A.
To know more about acid and bases, here:
https://brainly.com/question/27228111
#SPJ2
Can someone plz help-
Answer:
The answer is 3 :)
Answer: 3. a bottle that was broken into many small pieces
the ATOMIC WEIGHT OF ALUMINUM (AL) is 26.98. It has 14 neutrons. Aluminum has ?
a. an atomic mass of 13
b. an atomic number 13
c. 26 electrons
d. 26 protons
I believe b. an atomic number 13. is the answer.
The atomic weight of Aluminum (AL) is 26.98. It has 14 neutrons. Aluminum has an atomic number 13. Therefore, option B is correct.
What is atomic number?The atomic number of an element represents the number of protons in the nucleus of its atoms. Since the atomic number of an element is unique and determines its position in the periodic table, aluminum has an atomic number of 13.
The number of electrons in a neutral atom is equal to the number of protons, which in this case is 13. Therefore, aluminum has 13 electrons.
The atomic weight of aluminum (Al) is 26.98, which represents the weighted average mass of all the naturally occurring isotopes of aluminum, taking into account their relative abundances. The number of neutrons in an atom of aluminum is given as 14.
Thus, the correct option is B.
To learn more about the atomic number, follow the link:
https://brainly.com/question/16858932
#SPJ3
When [H+] = 4.0 × 10–9 M in water at 25°C, then
Kw =1.0×10–14.
b. pOH = 7.
c. [H3O+] = [OH–].
d. pH= 7
e. A-D are all correct
Answer:
a. Kw = 1.0 × 10⁻¹⁴
Explanation:
a. Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻
The ion-product of water (Kw) at 25 °C is:
Kw = [H₃O⁺][OH⁻] = 1.0 × 10⁻¹⁴
c. Considering [H⁺] = [H₃O⁺] = 4.0 × 10⁻⁹ M, the concentration of OH⁻ is:
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 2.5 × 10⁻⁶ M
b. We can calculate the pOH using the following expression.
pOH = -log [OH⁻] = -log 2.5 × 10⁻⁶ = 5.6
d. We can calculate the pH using the following expression.
pH = -log [H⁺] = -log 4.0 × 10⁻⁹ = 8.4
When [H+] = 4.0 × 10–9 M in water at 25°C, then the [tex]Kw =1.0\times 10^-^1^4.[/tex]
What is dissociation constant?
Kw is the dissociation constant or ionization constant of water.
The self-ionization of water will be
[tex]\rm 2 H_2O(l) = H_3O^+(aq) + OH^-[/tex]
The dissociation constant of the water at 25°C will be
[tex]\rm Kw = [H_3O^+][OH^-] = 1.0 \times 10^-^1^4[/tex]
Thus, the correct option is a. [tex]Kw =1.0\times 10^-^1^4.[/tex]
Learn more about dissociation constant
https://brainly.com/question/3657057
Match the definition with the correct term: 1/12th the mass of a carbon-12 atom.
Answer:
hydrogen atom but see the note below.
Explanation:
This is either the most common hydrogen ion or a hydrogen atom. It cannot be either of hydrogen's isotopes.
The formula for calculating power is work divided by time (power = work + time). What are two ways of stating the same relationship?
work = power + time
nwork s power x time
power
time = work x power
Opower workx time
time
Work
Answer:
See the answer below
Explanation:
The formula for calculating power is such that;
power = work/time
Two ways to restate the relationship between the 3 variables would be to make time and work the subject of the formula respectively.
1. When time if made the subject of the formula;
time = work/time
2. When work is made the subject of the formula;
work = power x time
d Which properties of plastics cause a problem when the container is empty?
Answer: Both of these are of great concern to human health. BPA is used in many things including plastic bottles and food packaging materials. Over time the polymer chains of BPA break down, and can enter the human body in many ways from drinking contaminated water to eating a fish that is exposed to the broken down toxins.
Explanation:
I think you will get it
How many moles of sulfate ions are in 756.91 mg of iron (III) sulfate?
Answer:
1 Answer. 1 mole of ferric sulfate contains 2 moles of iron, and 12 moles of oxygen atoms, and three moles of sulfate ions.Sep 29, 2016
Explanation:
I just wanted to say you guys on this app are no help. I have asked 4 question sin the past 1-2 hours and not one has been answered. If you know a lot about Chemistry please help me.
One of the waste byproducts of a nuclear reactor using uranium-235 is strontium-90 with half-life of about 28 years. If we have 100 pounds of this radioactive waste:
Answer:
(a) 140 years
(b) 3.125 pounds
Explanation:
QuestIons
(a) How long is five half-life
(b) How much radioactive strontium is left after five half-life
Given that:
Half-life is about 28 years; &
There are 100 pounds of this radioactive waste
Five half-life will be;
= 28 × 5
= 140 years
The amount of radioactive remaining after five half-life is:
[tex]= 100 \times( \dfrac{1}{2}) ^5[/tex]
= 100 × 0.03125
= 3.125 pounds
Which energy source releases the most carbon dioxide?
O solar
O wind
O nuclear
O coal
Answer:
Coal
Explanation:
Coal is by far the worst emitter, followed by natural gas, with solar, wind and nuclear all low-carbon.
Coal, a non-renewable energy source releases the most carbon dioxide into the atmosphere.
What are energy sources?Energy sources refers to the various sources in which energy for man's needs are obtained.
There are two types of energy sources:
Renewable energy sourcesNon-renewable energy sourcesThe non-renewable energy sources such as coal release large amounts of carbon dioxide until The atmosphere.
Therefore, Coal, a non-renewable energy source releases the most carbon dioxide into the atmosphere.
Learn more about non-renewable energy sources at: https://brainly.com/question/15415043
#SPJ2
11.
A sample of TNT, C-H5N306, has 7.30 1021 nitrogen atoms. Determine the numbers of
hydrogen atoms in this sample of TNT.
021
Answer:
1.22 × 10^22 H atoms
Explanation:
From this question, TNT has the chemical formula: C-H5N306. The number of nitrogen atoms in the TNT substance is said to be 7.30 × 10^21 atoms.
The number of hydrogen atoms in the same TNT substance can be got using mole ratio. Based on the chemical formula, the mole ratio of hydrogen to nitrogen is 5:3 i.e. H5N3.
This means that;
Number of atoms of hydrogen = 5/3 of the number of atoms of nitrogen.
Hence, number of H atoms = 5/3 × 7.30 × 10^21
number of H atoms = (7.30 × 5/3) × 10^21
number of H atoms = (36.5/3) × 10^21
number of H atoms = 12.1666 × 10^21
number of H atoms = 1.2166 × 10^22 atoms.
Approximately, number of H atoms in TNT is 1.22 × 10^22 atoms.
Rust has the same properties as iron
True
False
Answer:
false
Explanation:
Can anyone solve this?
Answer:
3P2O5:
P:6 O:15
5CO2
C:5 O:10
3C6H12O6
C:18 H:36 O:18
4C6H12
C:24 H:48
3Mg3(PO4)2
Mg:9 P:2 O: 8
4(NH4)2S
N:8 H:32 S:4
In what way is cellular respiration like breathing?
Answer:Cellular respiration is not the same as breathing, but they are closely related
Explanation: When you breathe in, you take in the oxygen your cells need for cellular respiration. When you breathe out, you get rid of carbon dioxide that your cells produce during cellular respiration.
If atomic size is the distance from the nucleus to the valence electrons, does the size of the atom get bigger or smaller as you go from period 1 to 3? Explain?
is pure water a solution
Answer: No because a solution is a homogeneous MIXTURE of two or more substances. Water is a pure substance. It is made of hydrogen and oxygen, but shares none of their properties. So it’s pure.
Explanation:
Describe the liquid state of matter and give an example besides water.
The density of a gas is 1.35 L what is the volume of the gas when the mass is 12.5 g
Answer:
9.26 LExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question we have
[tex]density = \frac{12.5}{1.35} \\ = 9.259259...[/tex]
We have the final answer as
9.26 LHope this helps you
Which of the following is true if the net force on an object is zero? (1 pt) a. The object must be at rest. b. The object’s speed will decrease. c. The object’s speed will increase. d. The object’s direction of motion can change, but its speed will not. e. None of the above.
Explanation:
the object must be at rest
The free flow of electrons is responsible for
Answer:
An electrical phenomenon is caused by flow of free electrons from one atom to another. The characteristics of current electricity are opposite to those of static electricity. Wires are made up of conductors such as copper or aluminum.
Explanation:
from google
Which of the following best defines an allotrope?
Question 1 options:
Crystalline forms
Carbon atoms
Different forms of the same element
Similar bonding arrangements between atoms
Answer:
hi buddy!! here is ur ans: carbon atoms
Question 5
2 pts
To determine the density of an irregularly shaped object, a student immersed the object in 32.2 mL of water in a graduated cylinder, causing the level of the water to rise to 37.8 ml. If the object had a mass of 12.4 g, what is the density of the object?
O 0.32 g/mL
O 1.4 g/mL
O 3.4 g/mL
O 2.2 g/mL
Help quick right answer gets brainliest !!
Answer:
Explanation:
2.2 g/mL is the answer.
PLEASE HELP I WILL MARK BRAINIEST ITS TIMED
Answer:
I assume air pollution.
Explanation:
If you incinerate something, usually fire or some kind of heating element is used. A byproduct of fire and/or burning is smoke, which can pollute the air.
Answer:
A. Air pollution
Explanation:
In the incineration Factories they produce items And Air pollution
How many atoms of each element are in the chemical formula NH4NO2?
1 nitrogen, 1 hydrogen, and 3 oxygen
O 1 nitrogen, 4 hydrogen, and 3 oxygen
2 nitrogen, 4 hydrogen, and 3 oxygen
O 5 nitrogen, 1 hydrogen, and 1 oxygen
How are the cells in our bodies organized? Cells are organized into ______ , _____
, and
_____ systems?
quick answer pls!
Answer:
Cell --> Tissues --> Organs ---> Organ System ---> Organism
100
80
100 mL
water vapor
Which statement describes what will happen if a student
pushes the plunger
to compress the water vapor?
A. The total number of water particles will increase.
B. The amount of energy in the water particles will decrease.
C. The amount of empty space between the water particles will
decrease.
O D. The total volume of the water particles will increase.
I will mark brainliest
Answer: c (the amount of empty space between the water particles will decrease)
Explanation: i got it right:)