Answer:
Joseph Black discovered carbon dioxide.
Explanation:
4 Al + 3 O2 -> 2 Al2O3 How much aluminum would be needed to completely react with 45 grams of Oz?
Answer:
50.6g Al would be needed
Explanation:
Based on the reaction:
4Al + 3O₂ → 2Al₂O₃
4 moles of aluminium react with 3 moles of oxygen to produce 2 moles of Al₂O₃
To solve this question we need to find the moles of 45g of O₂. Then using the chemical equation find the moles of Al and its mass:
Moles O₂ -Molar mass: 32g/mol-:
45g O₂ * (1mol / 32g) = 1.41 moles O₂
Moles Al:
1.41 moles O₂ * (4mol Al / 3mol O₂) = 1.875 moles Al
Mass Al -Molar mass: 26.98g/mol-:
1.875 moles Al * (26.98g / mol) =
50.6g Al would be needed
The amount of aluminum that would be required to completely react with 45 grams of O2 would be 50.59 grams.
From the balanced equation of the reaction:
[tex]4 Al + 3 O_2 ---> 2 Al_2O_3[/tex]
The mole ratio of Al to O2 is 4:3.
Mole of 45 grams of O2 = mass/molar mass
= 45/32
= 1.4063 moles
Equivalent mole of Al: 4 x 1.4063/3
= 1.875 moles
mass of Al = mole x molar mass
= 1.875 x 26.98
= 50.59 grams
More on stoichiometry calculations can be found here: https://brainly.com/question/22288091?referrer=searchResults
20 points to whoever can answer these 3 questions correctly
Pt. 3
Answer:
Explanation:
You can't award 20 points once you have awarded 5.
One
2K + Cl2 ==> 2KCl
It's True
There are 2 Ks and Cl2 has 2 atoms making up on the left.
On the right, 1 molecule of KCl has 1 Potassium and 1 Cl. But there are 2 molecules so between the two of them, there's 2 Potassiums and 2 Cl
Two
The reactant side is the Left side. Cl2 means there are 2 Cl atoms making Cl2. Answer B
Three
False: There are 2 but read below.
I really don't know how to answer that. It's not qualified enough. There are a total of 2 Chlorines on the right hand side when there are 2 molecules. I think you are intended to answer False, but don't be surprised if you get it wrong.
i/3 of 12 = 2/3 of
please help at 11 o'clock am it needs to be done
Answer:
6
Explanation:
This question is seeking for an equivalent of one expression. The first expression says 1/3 of 12, which means 1/3 × 12 = 4. To find 2/3 of a number that will give us 4, we say
Since; 1/3 of 12 is 4
Then, 4 = 2/3 of x, where x is the number, which when multiplied by two-third (2/3) will result to 4.
4 = 2/3 × x
4 = 2x/3
Cross multiply
2x = 3 × 4
2x = 12
x = 12/2
x = 6.
This means that; 1/3 of 12 = 2/3 of 6
Mention the reason why aquatic plants have air filled tissues.
Answer:
Aquatic plants have aur filled tissues to make them easy to float.....
Explanation:
It provides buoyancy
what are the the examples of amphoteric oxide
Answer:
Many metals (such as zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. Amphoterism depends on the oxidation states of the oxide. Al2O3 is an example of an amphoteric oxide.
Answer:
Lead (II) oxide and zinc (II) oxide
The following equation illustrates the chemical reaction that occurs in a plant.
Water + carbon dioxide + light energy → sugar + oxygen.
Based on the law of conservation of energy, what happened to the light energy in the reaction?
A) It was produced by the plant.
B) It was destroyed
C) It was changed into oxygen gas
D) It was converted into chemical energy stored in the sugar.
it was produced by a plant
Which of the following describes an adaptation?
A. a place where an organism lives
B. something that does not help an organism survive
C. something that improves an organism's ability to survive
D. a part of the animal's life cycle
Answer: C something that improves an organisms ability to survive
Answer:
C.
Explanation:
What happens to the air temperature if you add extra CO2?
Answer:
Adding more CO2 to the atmosphere will cause surface temperatures to continue to increase. However, more energy is absorbed in the weaker bands and in the wings of the strong band, causing the surface and lower atmosphere to warm further.
What types of chemical
reactions can change a toxic
chemical into one that is less
toxic
Answer:
Very toxic materials are substances that may cause significant harm or even death to an individual if even very small amounts enter the body.There are a number of very toxic materials that may be used in workplaces. Some examples include carbon monoxide, hydrogen sulfide, chlorine and sodium cyanide
Explanation:
here are generally four types of toxic entities; chemical, biological, physical and radiation: Chemical toxicants include inorganic substances such as, lead, mercury, hydrofluoric acid, and chlorine gas, and organic compounds such as methyl alcohol, most medications, and toxins.
The highly toxic chemical compounds can be changed to less toxic one by suitable substitution reactions where, a functional group which less hazardous but having the same biochemical properties are substituted for the new product.
What is toxicity?Toxicity of a chemical is its ability to cause serious health risks which can strike a single cell. Exposure to toxic chemicals may even lead to death. The dose of toxicity depends on the structure and reactivity of the chemicals.
Also the adverse effect of each toxic chemicals depends on the way of exposure, and the amount of exposed chemical. There are some methods to detoxify a living body if any toxic is intaken. Suitable antidotes are given for them.
The toxicity generated in a chemical might be originated from a certain structure or group. Thus, by altering that group for instance substituting a ring or removing them ir substituting a functional group that is responsible for the toxicity will make the chemical less toxic.
To find more on toxicity, refer here:
https://brainly.com/question/1563060
#SPJ2
Salinity affects density. Choose all of the correct answers.
options:
As water temperature decreases, water density increases.
As water temperature increases, water density increases.
As concentration of salt increases, water density also increases.
As concentration of salt decreases, water density also increases.
Answer:
1 and 3 i think so i could be wrong
Salinity affects density in the following instances:
A. As water temperature decreases, water density increases.
C. As concentration of salt increases, water density also increases.
What is salinity?Salinity can be defined as a measure of the amount of salt that is dissolved in a water body. Thus, it mainly measured in gram per liters.
What is density?Density can be defined as mass per unit volume. Also, it is measured in kilogram per cubic meters.
Based on scientific records, salinity affects density in the following instances:
As the temperature of water decreases, the volume increases and as such water density increases.As concentration of salt increases, water density also increases due to an increase in the mass of the water.Read more on salinity here: https://brainly.com/question/20283396
Powdered sodium carbonate reacts with a solution of sulphuric acid (H2SO4) to make a solution of sodium sulphate and water
carbon dixide is given
off.
Answer:
yes
Explanation:
Na2CO3 + H2SO4 --> Na2SO4 + H2O + CO2
Vitamin C has an empirical formula of C3H4O3 and a molecular mass of 176 amu. What is the molecular formula of vitamin C?
Answer:
(C3H4O3) x 2 = C6H8O6, the molecular formula for Vitamin C.
the more massive an object is, the more
Answer:
it have more more mass, gravitational potential energy
Explanation:
How many moles are present in 2.6 g of CO2?
Answer:
0.059 moles are present in 2.6 g of CO₂
Explanation:
Molar mass is the mass of one mole of a substance, which can be an element or a compound. That is, it is the amount of mass that a substance contains in one mole.
In this case, the mass of each element being:
C: 12 g/moleO: 16 g/molethen the molar mass of the compound is:
CO₂= 12 g/mole + 2*16 g/mole= 44 g/mole
Then you can apply the following rule of three: if by definition of molar mass 44 grams of CO₂ are present in 1 mole, 2.6 grams will be present in how many moles?
[tex]amount of moles=\frac{2.6 grams*1 mole}{44 grams}[/tex]
amount of moles= 0.059 moles
0.059 moles are present in 2.6 g of CO₂
What type of nonvisible light has a longer wavelength than the color red?
Answer:
i believe its blue
Explanation:
2) Where is Earth, exactly? Use this image to find our location. Earth is
Located in the
A) Norma arm
B) Outer arm
C) Orion spur.
D) Galactic bar
Answer:
C) Orion spur.
The Orion Arm is a minor spiral arm of the Milky Way Galaxy that is 3,500 light-years across and approximately 10,000 light-years in length, containing the Solar System, including Earth.
Does an increase in temperature always indicate that a chemical change has occurred?
I need a yes or no answer with a simple explanation, please...
Name a non-metal used to make electrode in the cell.
Answer:
graphite
Explanation:
graphite is also good conductor of electricity
How many moles are in 15.62g of P?
Answer:
[tex]\boxed {\boxed {\sf 0.5043 \ mol \ P}}[/tex]
Explanation:
To convert from moles to grams, we must use the molar mass. This is found on the Periodic Table. Look for Phosphorous or P.
Phosphorus (P): 30.973762 g/molWe can use this number as a ratio.
[tex]\frac{30.973762 \ g \ P }{1 \ mol \ P}[/tex]
Multiply by the given number of grams: 15.62
[tex]15.62 \ g \ P *\frac{30.973762 \ g \ P }{1 \ mol \ P}[/tex]
Flip the fraction so the grams of phosphorus cancel.
[tex]15.62 \ g \ P *\frac{1 \ mol \ P}{30.973762 \ g \ P }[/tex]
[tex]15.62 *\frac{1 \ mol \ P}{30.973762 }[/tex]
[tex]\frac{15.62 \ mol \ P}{30.973762 }[/tex]
Divide.
[tex]0.504297799 \ mol \ P[/tex]
The original measurement of grams has 4 significant figures, so our answer must have the same.
For the number we calculated, that is the ten thousandth place. The 9 in the hundredth thousandth place tells us to round the 2 to a 3.
[tex]0.5043 \ mol \ P[/tex]
There are 0.5043 moles of phosphorus in 15.62 grams.
What will happen when iodine solution is added to a solution of potassium bromide?
A)No reaction
B)Solid iodine is produced
C)Bromine is produced
Answer:
C) Bromine is produced
Explanation:
When iodine chemically reacts with potassium bromide then it will lead to the formation of potassium iodide and bromine. This reaction is actually a single displacement reaction in which bromine from potassium bromide is displaced by iodine atom.
When iodine solution is added to potassium bromide solution ,bromine is produced. It is an example of displacement reaction.
What are displacement reactions ?
Displacement reactions are chemical reactions in which one element present in a compound is replaced by another element.The reaction generally takes place between a molecule and a compound.
During the reaction, the anion of compound is replaced by the molecule and the anion of the compound is transformed into a molecule.When iodine molecule in form of solution is reacted with solution of potassium bromide solution of potassium iodide is obtained.
During this reaction anion of potassium bromide that is bromine is replaced by iodine forming solution of potassium iodide and molecule of bromine is liberated in the form of gas.
Learn more about displacement reactions,here:
https://brainly.com/question/13328989
#SPJ6
Which electromagnetic wave has the longest
wavelength? Describe the energy level and
frequency of this wave.
Answer:
radio waves
Explanation:
which has the longest wavelength and lowest frequency and energy. Ultraviolet light (UV) is divided into three regions: UV A, wavelength = 400 - 320 nm UV B, wavelength = 320 - 280 nm
How many grams are in 1.11 molecules of N2?
Answer:
15.547437000000029
Explanation:
what is the percent of just the oreo(out of 100%) from the total mass of these 3 cookies combined
Answer:
Percent mass of oreo = 35.11%
Explanation:
Given:
Mass of oreo = 17.1
Mass of 1st cookie = 16.2
Mass of 3rd cookie = 15.4
Find:
Percent mass of oreo
Computation:
Total mass = Mass of oreo + Mass of 1st cookie + Mass of 3rd cookie
Total mass = 17.1 + 16.2 + 15.4
Total mass = 48.7
Percent mass of oreo = [Mass of oreo/Total mass]100
Percent mass of oreo = [17.1 / 48.7]100
Percent mass of oreo = 35.11%
What can be inferred from the graph?
do the yoga boi TUT yooooooooooooooooooooo9ooooooooot
2Na(s) + Cl2(g) → 2NaCl(s)
Which of the following choices shows the correct Lewis electron-dot diagram for a molecule of chlorine, Cl2?
Answer: 2!
Explanation:
The best lewis structure for [tex]Cl_2[/tex] is in option 2.
Na or sodium is the cation in the reactant.
Cl or chlorine is the anion in the reactant side.
NaCl is the product of the reaction.
Lewis Structure is a very simplified representation of the valence shell electrons in a molecule. It is used to show how the electrons are arranged around individual atoms in a molecule. Electrons are shown as "dots" or for bonding electrons as a line between the two atoms.
Chlorine is a group VIIA element in the periodic table and contains seven electrons in its last shell.
Valence electrons are given by chlorine atoms = [tex]7\times2=14[/tex]
Total valence electrons = 14
So, each of Cl is surrounded by three pairs of dots, connected by a single line. So, the best lewis structure for [tex]Cl_2[/tex] is in option 2.
To know more about:-
brainly.com/question/20300458
Electrons can occur only in specific
Answer: Electrons have wavelike motion and are restricted to certain energy states associated with specific wavelengths.
Which coefficient placed before HCl will balance the following
equation? Zn+HCI ZnCl2 + H2
Explanation:
Given chemical equation
Zn + HCL ➡ ZnCl2 + H2
Now balancing
Zn + 2HCL ➡ ZnCl2 + H2
Hope it will help :)❤
The coefficient placed before HCl which makes the equation to be balanced is 2.
To know which coefficient will be placed before HCl to balance the equation, we shall simply balance the equation given from the question.
Zn + HCl —> ZnCl₂ + H₂
The above equation can be balance as illustrated below:
There are 2 atoms of H on the right side and 1 atom on the left side. It can be balance by writing 2 before HCl as shown below:
Zn + 2HCl —> ZnCl₂ + H₂
Now, the equation is balanced.
From the balanced equation above, the coefficient written before HCl which makes the equation to be balance is 2.
Learn more: https://brainly.com/question/13025541
2) A student determined the melting point of a substance to be 55.2DC. If the accepted value
is 50.1C, what is the percent error in the student's determination?
A) 12.0 B) 5.10 C) 10.2 D) 9.24
Answer:
C) 10.2
Explanation:
Formula: Actual-Expected/Expected
The actual was 55.2 while the expected was 50.1
55.2-50.1/50.1=0.101796407 * 100= 10.2%
The percentage error in the student's determination is 10.2%
The correct answer to the question is Option C. 10.2
From the question given above, the following data were obtained:
Measured value = 55.2 °C
Accepted value = 50.1 °C
Percentage error =?Next, we shall determine the absolute error. This can be obtained as follow:
Measured value = 55.2 °C
Accepted value = 50.1 °C
Absolute error =?Absolute error = |Measured – Accepted|
Absolute error = |55.2 – 50.1|
Absolute error = 5.1Finally, we shall determine the percentage error.
Absolute error = 5.1 °C
Accepted value = 50.1 °C
Percentage error =?[tex]Percentage error = \frac{Absolute error }{Accepted value} * 100\\\\= \frac{5.1}{50.1} * 100\\\\[/tex]
Percentage error = 10.2%Therefore, the percentage error in the student's determination is 10.2%.
The correct answer to the question is Option C. 10.2
Learn more: https://brainly.com/question/17441904
what is law of conservation of mass
Answer:
Mass in an isolated system can neither be destroyed nor created.
Explanation:
In a chemical reaction, mass can neither be created nor be destroyed.
3. How many grams of water will be produced from 15.0 grams of Methane? *
CH4 +2 02 → CO2 + 2H2O