Answer:
B
Explanation:
Oxygen (O2) is made up of two oxygen atoms but, just of one kind of atom oxygen (O), So it's an element. Water (H2O) is made up of two hydrogen atoms (H) and one oxygen atom (O), so it's a compound
does boron or lithium have a greater first ionization energy ?
Answer:
beryllium has a higher ionization energy because its radius is smaller. boron has a higher ionization energy because its radius is smaller.
what will occurs during electrolysis of dilute sulphuric acid
Answer:
In the electrolysis of dilute sulfuric acid, which electrolysis in aqueous solution to form hydrogen ions, H⁺, and sulfur IV ions SO₄²⁻ in the presence of H⁺ and OH⁻ ions from the water molecules
At the anode
The anode, positive electrode, attracts the negative OH⁻ and SO₄²⁻ ions where the OH⁻ gives up electrons to form water molecules and oxygen as follows;
4OH⁻ → 2H₂O + O₂ + 4e⁻
At the cathode
The positive H⁺ ions from the water molecules and the acid are attracted to the cathode where they combine with 2 electrons to form hydrogen gas as follows;
2e⁻ + 2H⁺ → H₂ (gas)
Explanation:
which of the following would form an ionic bond?
a.strontium and oxygen
b. sulfur and oxygen
Based on the information from the movie, what can you
Conclude about the common chemical compound on
earth?
A
It's oxygen
B
its hydrogen gas
C
It's carbon dioxide
D
It's water
Answer:
a
Explanation:
it's the most common thought of element when you need a compound from earth
What's the ABBREVIATED electron configuration for cobalt?
Answer:
Cobalt/Electron configuration
Explanation:
[Ar] 3d7 4s2
During a beta decay reaction, a(n)
is emitted from the reactant.
helium nucleus
O electron
O hydrogen nucleus
O proton
24. The only thing that Carbon, nitrogen and oxygen want is
To bond with another atom
b. To have eight electrons in their outer shell
To be left alone
To donate a few electrons
C.
Which one of the following is a pure substance? A. Sea water B. sodium C. smoke and D. Soft drink
Answer:
B. Sodium
Explanation:
The composition of sea water, smoke, and soft drinks are not consistent, and you can separate the parts that make up each. Sodium has a definite and consistent composition, so it is a pure substance.
A 25.00 ml solution containing 0.033 M sodium acetate is titrated with a 0.098 M solution of HCl. How mar
milliliters of HCl are required to reach the endpoint?
Answer:
[tex]8.42\ \text{mL}[/tex]
Explanation:
When the endpoint is reached the millimoles of sodium acetate and HCl will be equal.
[tex]\text{Volume of sodium acetate}=25\ \text{mL}[/tex]
[tex]\text{Molarity of sodium acetate}=0.033M[/tex]
[tex]\text{Molarity of HCl}=0.098M[/tex]
[tex]\text{Millimoles of sodium acetate}=25\times 0.033=0.825\ \text{mmol}[/tex]
Let [tex]V=\text{Volume of HCl}[/tex]
[tex]\text{Millimoles of HCl}=0.098V[/tex]
At end point the millimoles will be equal to that of sodium acetate
[tex]0.825=0.098V\\\Rightarrow V=\dfrac{0.825}{0.098}\\\Rightarrow V=8.42\ \text{mL}[/tex]
The volume of HCl required is [tex]8.42\ \text{mL}[/tex].
The volume of HCl required to required to reach endpoint is 8.42 mL
From the question,
We are to determine the volume of HCl required to reach endpoint
First, we will write a balanced chemical equation for the reaction.
The balanced chemical equation for the reaction is
CH₃COONa + HCl → CH₃COOH + NaCl
This means
1 mole of sodium acetate is required to completely neutralize 1 mole of HCl
Now, we will determine the number of moles of sodium acetate present
Using the formula
Number of moles = Concentration × Volume
Concentration of sodium acetate = 0.033 M
Volume of sodium acetate = 25.00 mL = 0.025 L
∴ Number of moles of sodium acetate present = 0.033 × 0.025
Number of moles of sodium acetate present = 0.000825 mole
Now,
Since, 1 mole of sodium acetate is required to completely neutralize 1 mole of HCl
Then,
0.000825 mole of sodium acetate would be required to completely neutralize 0.000825 mole of HCl
∴ The number of moles of HCl needed is 0.000825 mole
Now, for the volume of 0.098 M HCl required to reach endpoint
Using the formula
[tex]Volume = \frac{Number\ of\ moles}{Concentration}[/tex]
∴ Volume of HCl required to required to reach endpoint = [tex]\frac{0.000825}{0.098}[/tex]
Volume of HCl required to required to reach endpoint = 0.008418367 L
Volume of HCl required to required to reach endpoint = 8.418367 mL
Volume of HCl required to required to reach endpoint ≅ 8.42 mL
Hence, the volume of HCl required to required to reach endpoint is 8.42 mL
Learn more here: https://brainly.com/question/9698827
1. The behavior that occurs when a wave bends as it changes media is known as
a) absorption
b) refraction.
c) reflection
d) transmission
Answer:
b refraction
Explanation:
i saw on nasa's website lol
How many atoms in:
1. NiO -
2. CuO -
3. BaO -
(Pls help ill give brainliest!)
Answer:
I think it might be:
NiO=2
CuO=4
BaO=2
Explanation:
Hope this helps.
How many grams of lead would be required to make 119 grams of water
Answer:
684
Explanation:
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 684 g of lead would be required to make 119 grams of water.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
The balanced equation for the given reaction can be written as below
Pb + PbO[tex]_2[/tex] + 2H[tex]_2[/tex]SO[tex]_4[/tex] [tex]\rightarrow[/tex]2PbSO[tex]_4[/tex] + 2H[tex]_2[/tex]O
Mathematically,
The mole ratio between lead and water is 1:2
(119 g H2O) / (18.01532 g H2O/mol) x (1 mol Pb / 2 mol H2O) x (207.21 g Pb/mol) = 684 g Pb
The mass of lead comes out to be 684 g.
Therefore, 684 g of lead would be required to make 119 grams of water.
To know more about mole, here:
https://brainly.com/question/15209553
#SPJ2
the highest level of organization is
.Answer:
.Marie Kondo
Answer:
Federal Government
Explanation:
:)))))))))
✌❤✌❤
9. Gasoline burns easily if ignited
a) Chemical property
b) Chemical change
c) Physical property
O d) Physical change
Answer:
I think it is chemical change
Elements with atomic numbers 7 and 83 have how many valence electrons? *
5 and 5 valence electrons
4 and 8 valence electrons
2 and 2 valence electrons
7 and 83 valence electrons
Explanation:
element with atomic numbers 7 and 83 have 5 and 5 valence electrons
After 4797 years, how much of the original 250 g of radium-226 remains, if
the half-life of radium-226 is 1599 years? *
125 grams
62.5 grams
31.3 grams
O 75.0 grams
Answer:
31.3grams
Explanation:
The amount of a radioactive element that remains, N(t), can be calculated by using the formula;
N(t) = N(o) × 0.5^{t/t(1/2)}
Where;
N(t) = mass of substance remaining
N(o) = mass of original substance
t(1/2) = half-life of substance
t = time elapsed
From the provided information; N(t) = ?, N(o) = 250g, t(1/2) = 1599 years, t = 4797 years
N(t) = 250 × 0.5^{4797/1599}
N(t) = 250 × 0.5^(3)
N(t) = 250 × 0.125
N(t) = 31.25g
N(t) = 31.3grams
Fill in the coefficients that will balance the following reaction:
(Note: Use 1 as coefficient where appropriate.)
CH4 +
O2 →
CO2 +
H2O
Answer:
CH4 + 2 O2 → CO2 + 2 H2O
Explanation:
There are one mole of O2 on the left side and on the right side there are three moles of O2. And to fix it you would need to make it two moles of O2 to have four molecules of O2 on the left side. Then you would make two moles of H2O to have a total of four moles of O2 on the right. Therefore, CH4 + 2 O2 → CO2 + 2 H2O is the answer.
Answer:
1,2,1,2
Explanation:
hope this helped!
Do all irreversible reactions go to completion? If so why?
Answer:
True
Explanation:
All irreversible reactions go to completion because the process cannot proceed in the backward direction.
A reversible reaction is one that does not go into completion in one direction.
An irreversible direction completely uses up the reactants to form the products and goes into completion.
These reactions can only proceed in one direction and not both.
Is buoyancy a physical or chemical property?
a serving of cheese its releases 130kcal when digested. if this energy was transferred to 2.5kg of water at 27 degrees celsius, what would the final temperature be?
The final temperature : 79.07°C
Further explanationHeat transferred can be formulated
Q=m.c.ΔT
Q= heat, J
m=mass,g
c=specific heat, for water 4.18 J/g C
ΔT = temperature
Heat transferred : 130 kcal
1 kcal = 4186 J
130 kcal =
[tex]\tt 130\times 4186=544180~J[/tex]
mass = 2.5 kg =2500 g
t₁=27 °c
The final temperature :
[tex]\tt 544180=2500\times 4.18\times (t_2-27)\\\\t_2-27=52.07\\\\t_2=79.07^oC[/tex]
it is sunny today is that whether or climate this isn't chemistry but...
Answer:
weather
Explanation:
Some properties of matter depend on how much matter there is. Put an X next to all of the statements you think are true about properties of matter.
Answer:
Its B and D :)
Explanation:
I saw the answer key.
What is one disadvantage of a unicellular organisms?
Answer:
Unicellular organisms don't live as long and multicellular organisms. ... Disadvantages- Unicellular organisms only have one cell that is used to function their entire being. Short life span, can't grow lager then multicellular organisms.
HERE YA GO FORTNITE KID
How do you differentiate a neutral solution like water and a strong acid solution like battery acid?
Answer:
If the pH of a solution is less than 7, the solution is called acidic; if the pH is about 7, the solution is neutral; if the pH is greater than 7, the solution is is called basic. In an acidic solution, then, the concentration of hydrogen ions is greater than the concentration of hydroxide ions.
Explanation:
Not sure about the context of the question, but you can check with a ph scale tester.
please help in this question
In the reaction 2Li(s) + 2H20(1) 2LIOH(aq) + H2(g), which compound is in
the liquid state?
A. H20
B. LiOH
C. Li
O D. H2
Answer:
liquid state is an intermediate phase between solid and gas phase
Answer is A. H20
Answer:
H2O
Explanation:
As H2 is a gas, and the question asks for the liquid state, it'd be H2O.
4. The nucleus of an atom is positively charged due to
A. electrons b. neutrons C. proton D. Ion
Answer:
Protons
Explanation:
Electrons have a negative charge which are found in shells around the nucleus. The nucleus consists of protons and neutron and the neutron has a neutral charge.
Do the molecules in cold things move fast or slow?
Answer:
slow
Explanation:
according to kinetic molecular theory,as the temperature decreases the kinetic energy of molecules decreases
t∝k.eStudents measuring the mass of a metal block record 2.985 g, 3.051 g, 3.102
g, and 3.211 g. Which other measurement of the block's mass would be most
precise?
A. 2.804 g
B. 3.1159
C. 3.418 g
D. 3.509 g
Answer:C - 3.115 g
Explanation:Correct
Please give formulas of how you solved I only need help on a but if you can do all that I would appreciate that.
Answer:
3.1 moles of ammonia
18.67× 10²³ molecules
Mass = 52.7 g
Explanation:
Given data:
Number of atoms of hydrogen = 5.68×10²⁴ atoms
A) Number of molecules of ammonia = ?
Solution:
First of all we will calculate the number of moles of hydrogen.
1 mole = 6.022× 10²³ atoms
5.68×10²⁴ atoms × 1 mol / 6.022× 10²³ atoms
0.94×10¹ mol
9.4 moles of hydrogen
Moles of ammonia:
3 moles of hydrogen are present in one mole of ammonia.
9.4 moles of hydrogen = 1/3×9.4 =
3.1 moles of ammonia
Number of molecules of ammonia:
1 mole contain 6.022× 10²³ molecules.
3.1 mol × 6.022× 10²³ molecules / 1 mol
18.67× 10²³ molecules
c) Mass of sample = ?
Mass = number of moles × molar mass
Mass = 3.1 moles × 17 g/mol
Mass = 52.7 g