Answer:
The disc is made of silver.
Explanation:
To solve this question we need to calculate the metal's density. To do so we need its mass (already given by the problem, 1.31 kg) and its volume.
Following Archimedes' principle, the volume of water displaced by the disk is equal to the disk's volume. This means the metal's volume is 125 mL.
Now we convert 1.31 kg into g, to better compare with the given options:
1.31 kg * 1000 = 1310 gFinally we calculate the metal's density:
Density = Mass / VolumeDensity = 1310 g / 125 mL = 10.48 g/mLLooking at the densities given by the problem, the closest one is silver.
What is the concentration of a stock solution if 20 mL was used to make 400 mL of a 1.44
M solution?
30 M
40 M
50 M
5M
Given :
Volume of stock solution, [tex]V_s = 20\ mL[/tex].
Volume of diluted solution, [tex]V_d = 400 \ mL[/tex].
Molarity of diluted solution, [tex]M_d = 1.44\ M[/tex].
To Find :
The concentration of the stock solution.
Solution :
We know, dilution factor is given by :
[tex]D.F=\dfrac{V_ {diluted}}{V_{stock}}[/tex] ....1)
and [tex]D.F= \dfrac{M_{stock}}{M_{diluted}}[/tex] ....2)
Putting volume in above equation, we get :
D.F = 400/20
D.F = 20
Putting value of D.F in equation 2) we get :
[tex]\dfrac{M_{stock}}{M_{diluted}} = 20\\\\M_{stock} = 20\times 1.44\\\\M_{stock} =28.8\ M[/tex]
The concentration of stock solution is nearest to 30 M.
Therefore, the correct option is 1) 30 M.
Show your work with good use of units, rounding, and significant figures. [Hint: it is good practice to show the value of your answer before you round off to the final answer with the correct significant figures!]
(8 points) How much heat is required to convert 10.00 g of ice at –20.00°C to water at 25°C. The specific heat of ice is 2.09J/g°C; the specific heat of water is 4.182 J/g°C; the heat of fusion is 333.0 J/g.
Group of answer choices
Heat required : 4.8 kJ
Further explanationThe heat to change the phase can be formulated :
Q = mLf (melting/freezing)
Q = mLv (vaporization/condensation)
Lf=latent heat of fusion
Lv=latent heat of vaporization
The heat needed to raise the temperature
Q = m . c . Δt
1. heat to raise temperature from -20 °C to 0 °C
[tex]\tt Q=10\times 2.09\times (0-(-20)=418~J[/tex]
2. phase change(ice to water)
[tex]\tt Q=10\times 333=3330~J[/tex]
3. heat to raise temperature from 0 °C to 25 °C
[tex]\tt Q=10\times 4.18\times (25-0)=1045~J[/tex]
[tex]\tt Q~tot=418+3330+1045=4793~J\rightarrow rounding~and~2~sig~figs=4.8~kJ[/tex]
I will give you Brainly if you awser correct if your gonna awser for points pl put I don’t know
Answer:
C
Explanation:
A compound is 39.97% carbon, 13.41% hydrogen, and 46.62% nitrogen. What is the empirical formula?
Answer:
CH4N
A compound is 39.97% carbon, 13.41% hydrogen, and 46.62% nitrogen.
Explanation:
Hope this helps.
Answer: CH4N is correct
Explanation:
39.97% carbon
13.41% hydrogen
46.62% nitrogen.
Observe: Look at the red lithium atom and the blue oxygen atom. Recall that most atoms are stable when their outermost ring has eight electrons. (Some atoms, such as lithium and beryllium, are stable when their outermost ring has two electrons.)
How many electrons will the lithium atom give up to become stable?
1. eight
2. seven
3. two
4. one
Answer:
4. one
Explanation:
You are sitting in the central park bleachers of a Major League baseball park. You see a batter strike a pitched ball. About 0.4 seconds later you hear the contact between the bat and the ball. In terms of the properties of light and sound waves, how do you explain the difference in the communications you receivedbabout the same event?
Answer:
See the answer below
Explanation:
The speed of light in air and space is faster than the speed of sound in the same media. Light travels with a speed of approximately 3 x [tex]10^8[/tex] m/s while sound can only travel at 343 m/s (at 20 [tex]^oC[/tex]).
Consequently, the visuals of a batter striking a pitched ball which travel by light and is perceived through the eyes would be seen before the sound of the strike.
The difference in the speeds of light and that of sound largely explains the difference in the communication received about seeing a batter striking a pitched ball before hearing the sound of the strike
Explain why the electron configuration of 2-3-1 represents an atom in an excited state?
Answer:
See explanation
Explanation:
If we look at the electron configuration closely, we will discover that the element must have had a ground state electron configuration of 2,4.
This is because, the innermost shell usually holds two electrons while the outer shells hold eight electrons each. The four electrons must be accommodated in the second shell in the ground state configuration of the compound.
However, when the atom is excited, one electron from this shell may move to the third shell to give the excited state configuration 2-3-1 as shown in the question.
how much heat is absorbed when 15.0 g of liquid water is heated until the temperature increases by 16.0.
What do you think caused this land formation ?
The gas could be which of the following? Select all that apply. Hint: These gases are more dense than air. Nitrogen Neon Argon Carbon Dioxide Helium Hydrogen Propane Carbon Monoxide
Answer:
nitrogen, oxygen, carbon dioxide, argon, hydrogen, helium
Explanation:
Which of the following atoms has the largest radius?
a. lithium
b. lead
C. cesium
d. fluorine
e. carbon
Explanation:
first one, a. lithium. it's the largest
atoms are so small that approximately _______ of them can fit at the end of a needle?
Answer:
5 million million atoms can fit at the end of a needle
Answer:
Let's just say 5 million million hydrogen atoms could fit at the end of a needle.
Explanation:
Atoms are 100 picometers, and to compare, the amount of even 1 centimeter, a calculator can't even figure out how many picometers are in a centimeter because there is just too much picometers.
another science question plz answer ASAP b/c its timed
Answer:
D
Explanation:
What will a medium mass star become at the very end of its life cycle
Please help! Will mark brainliest!
Answer:
A
Explanation:
Using the model of the periodic table, which element pictured represents an unreactive gas?
Answer:
2
Explanation:
Nobel gasses are not reactive and are the far right group on the periodic table. This is because they have a full valence electron shell which is the most stable electron configuration. Most reactions occur in order for an atom to fill its valence shell and since they already have a full valence shell there is no reason for them to react.
Please help I will mark brainy
Answer:
the answer is c I took the test
Help plz 15 pointsss
You mix 15g of water with 10 grams of sodium chloride. After the reaction occurs, how
many grams of your new substance do you have?
A) 15g
B) 25g
C) 20g
D) not enough information
Answer:
B) 25g
Explanation:
Every reaction must follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
In given example:
Water + sodium chloride → Product
15 g + 10 gram = 25 g
25 g = 25 g
FOR 50 POINTS & A BRAINIST*
1.) For an atom of sulfur, there are
A.) two electron shells with 6 valence electrons
B.) three electron shells with 6 valence electrons
C.) four electron shells with 6 valence electrons
D.) five electron shells with 6 valence electrons
2.) Which atom has four electron shells with 7 valence electrons?
A.) F
B.) CI
C.) Br
D.) I
3.) Which atom has three electron shells with 8 electrons in its outermost orbit?
A.) He
B.) Ne
C.) Ar
D.) Kr
4.) Which method should be used to draw electrons that are involved in a collision during a chemical reaction?
A.) Bohr's model
B.) Lewis dot model
C.) Addition model
D.) Subtraction model
Answer:
1. B
2. C
3. C
4. B
Explanation:
1. An atom of sulfur has an atomic number of 16. It has three electron shells and six valence electrons, therefore, it belongs to period 3, group VIA of the periodic table
2. Bromine has an atomic number of 35. It belongs to period 4 group VIIA of the periodic table. Therefore, it has four electron shells and seven valence electrons.
3. Argon has an atomic number of 18. It belongs to period 3, group IVA of the periodic table. Therefore, it has three electron shells and eight valence electrons.
4. The Lewis dot model use structures that represent the valence electrons of atoms within a molecule existing as lone pairs or when involved in bonding. They can be used to draw electrons that are involved in a collision during a chemical reaction.
an atom has 11 protons, 12 neutrons, and 11 electrons. what is the charge of the atoms nucleus?
A) +11
B) -11
C) 0
D) 23
Answer:
Since sodium has 11 protons, the number of neutrons must be 23 – 11 = 12 neutrons.
Explanation:
Which of the following atoms has the highest first
ionization energy?
a. helium
6. potassium
d. hydrogen
e. carbon
Answer:
Helium
Explanation:
The first ionization energy varies in a predictable way across the periodic table.
How much oxygen (O) is in 5.41 × 106 atoms of oxygen
Answer:
They show you how to do it sweetie
Explanation:
123456789 Common math
Science hmk due tmr morning need help!! pls answer all 3 and number which one is which for example...
1.j
2.j
3.j
what is the density of a liquid if it's volume is 125 mL and it's mass is 50g?
Answer:
0.4g/ml
Explanation:
density= mass/volume
density=50g/125ml
density=0.4g/ml
A reversible reaction is said to be in equilibrium when
A)
all reactions stop leaving some reactant unused.
B)
the reaction goes to completion and no reactants are left.
9)
the rate of the backward reaction equals the rate of the forward reaction.
D)
the reaction rate of the backward reaction becomes larger than the rate of
the forward reaction.
Answer: C) the rate backward reaction equals the rate of the forward reaction.
Explanation:
Think about how particles are arranged inside atoms. Please name and describe those three particles, and describe how the particles are arranged inside atoms. Some topics to include are: the charge of the particles, the mass of the particles, and where the particles are located.
How do HOT AIR BALLOONS work when ascending and descending explain in terms of gas behavior?
Answer: Animation: Burning gas makes the air inside the balloon less dense, producing an upward force or lift. 1) A hot air balloon stays on the ground (or descends) when the air inside it is too cool. ... 3) When the air is hotter still, the balloon rises because the lift force is greater than the weight.
Explanation:
Common sense
Carbon tetrafluoride, CF, contains four identical C-F bonds. Fluorine is more
electronegative than carbon. How will this impact each of the bonds between carbon and
fluorine?
a. The electrons in each C-F bond will be more attracted to the carbon atom.
b. The electrons in each C-F bond will be attracted equally to both atoms.
C. The electrons in each C-F bond will be more attracted to the fluorine atom.
d. The electrons in each C-F bond will separate easily.
Answer:
C. The electrons in each C-F bond will be more attracted to the fluorine atom.
Why are you able to smell things across a room or form great distances
Answer:
We smell hot food from distance because of the diffusion process. Diffusion is the spreading out and intermixing of particles From one substance into another substance due to the movement of particles.
Explanation: