Chemistry Middle School
Answers
Answer 1
Answer:
3
Explanation:
According to law of conservation of mass energy and charge the mass energy and charge will remain conserved.
Answer 2
I believe the answer would be 3( conserved)
Related Questions
Explain the relationship between plate tectonics and volcanos
Answers
Answer:
Plates sliding past each other cause friction and heat. Subducting plates melt into the mantle, and diverging plates create new crust material. Subducting plates, where one tectonic plate is being driven under another, are associated with volcanoes and earthquakes.
Explanation:
Look at the four positions of Earth with respect to the sun. Florida is in the Northern hemisphere. At what position of Earth will Florida experience the first day of spring? (2 points) Question 41 options: 1) Position 1 2) Position 2 3) Position 3 4) Position 4
Answers
Answer:
2) Position 2 3
Explanation:
Which of these statements is correct about P and S seismic waves? (2 points) Question 40 options: 1) Both P and S waves travel along Earth's surface and their amplitude decreases with depth into Earth. 2) Both P and S waves travel with the same speed through Earth and their amplitude increases with time. 3) P waves are radiated along a single direction but S waves are radiated along all directions. 4) P waves change the volume of the medium through which they travel but S waves do not change the volume of the medium
Answers
Answer:
3
Explanation:
Primary waves are radiated along a single direction, but secondary waves are radiated along all directions. That is why the P waves can take place in almost all mediums such as solid, liquid and air, unlike the S waves that are transverse and only travel through solid mediums
Answer:
Option 3
Explanation:
I took the test
A hurricane warning has been issued in a location in Florida. What would people in the location most likely do? (2 points) Question 20 options: 1) turn on all major appliances in the house 2) remove fuel from their cars and generators 3) check and replenish emergency supplies 4) sit on the floor beside windows and doors
Answers
Answer:3 check and replenish emergency supplies
Explanation: This one is the only one that is not counter intuitive.
If the atmospheric pressure in the laboratory is 1.2 atm, how many moles of gas were in each syringe? Air(H2O) syringe
Room temperature water at 21.3 degrees Celsius
Volume of 5.1 mL
Hydrogen(H2) syringe
Room temperature water at 21.3 degrees Celsius
Volume of 5.2 mL
Answers
Answer:
A: 2.525 x 10⁻⁴ mol
B: 2.583 x 10⁻⁴ mol
Explanation:
Part A:
Data Given:
- Temperature of water (H₂O) = 21.3°C
Convert Temperature to Kelvin
T = °C + 273
T = 21.3 + 273 = 294.3 K
- volume of (H₂O) gaseous state = 5.1 mL
Convert mL to liter
1000 mL = 1 L
5.1 ml = 5.1/1000 = 0.0051 L
- Pressure = 1.2 atm
- no. of moles = ?
Solution
no. of moles can be calculated by using ideal gas formula
PV = nRT
Rearrange the equation for no. of moles
n= PV / RT . . . . . . . . . (1)
where
P = pressure
V = Volume
T= Temperature
n = Number of moles
R = ideal gas constant
where
R = 0.08206 L.atm / mol. K
Now put the value in formula (1) to calculate no. of moles of
n = 1.2 atm x 0.0051 L / 0.08206 L.atm.mol⁻¹. K⁻¹ x 294.3 K
n = 0.0061 atm.L / 24.162 L.atm.mol⁻¹
n = 2.525 x 10⁻⁴ mol
no. of moles of gas (H₂O) = 2.525 x 10⁻⁴ mol
_______________
Part B:
Data Given:
- Temperature of water (H₂) = 21.3°C
Convert Temperature to Kelvin
T = °C + 273
T = 21.3 + 273 = 294.3 K
- volume of (H₂) gas = 5.2 mL
Convert mL to liter
1000 mL = 1 L
5.2 ml = 5.2/1000 = 0.0052 L
- Pressure = 1.2 atm
- no. of moles = ?
Solution
no. of moles can be calculated by using ideal gas formula
PV = nRT
Rearrange the equation for no. of moles
n= PV / RT . . . . . . . . . (1)
where
P = pressure
V = Volume
T= Temperature
n = Number of moles
R = ideal gas constant
where
R = 0.08206 L.atm / mol. K
Now put the value in formula (1) to calculate no. of moles of
n = 1.2 atm x 0.0052 L / 0.08206 L.atm.mol⁻¹. K⁻¹ x 294.3 K
n = 0.0062 atm.L / 24.162 L.atm.mol⁻¹
n = 2.583 x 10⁻⁴ mol
no. of moles of gas (H₂) = 2.583 x 10⁻⁴ mol
Which of these statements best explains why the ocean currents in the Northern hemisphere tend to move in the clock-wise direction? (2 points) Question 14 options: 1) The currents deflect to the right due to the rotation of Earth. 2) The change in gravitational forces causes currents to move towards right. 3) The deflection of winds to the left causes the currents to move in the opposite direction. 4) The altered wind speed due to Earth's rotation causes the movement of ocean water.Which of these statements best explains why the ocean currents in the Northern hemisphere tend to move in the clock-wise direction? (2 points) Question 14 options: 1) The currents deflect to the right due to the rotation of Earth. 2) The change in gravitational forces causes currents to move towards right. 3) The deflection of winds to the left causes the currents to move in the opposite direction. 4) The altered wind speed due to Earth's rotation causes the movement of ocean water.
Answers
Answer: Option (1) is the correct option that is currents deflect to the right due to the rotation of Earth.
Explanation:
The water on the surface of ocean is moved by winds that blow in certain direction because of the Coriolis effect and spinning of the Earth that's why ocean currents in the Northern hemisphere tend to move in the clock-wise direction.
Scientists have observed huge bubbles of gas ejecting from the sun. Which of these events would most likely occur due to this solar condition? (2 points) Question 2 options: 1) decrease in wind velocity 2) decrease in the gravitational force 3) increase in the average temperature of Earth 4) increase in the amount of helium in the atmosphere
Answers
Answer:
3) increase in the average temperature of Earth
Explanation:
Coronal mass ejections or CME is the phenomena described as "Scientists have observed huge bubbles of gas ejecting from the sun". Whilst CMEs can happen alongside solar flares, it is also important to know that they can occur by themselves (independently). Solar flares refers to the abrupt release of energy kept in twisted magnetic fields caused by explosions on the Sun.
When these solar flares hit the earth, the gases (gas molecules) in the upper atmosphere such as nitrogen and water vapor are broken up and freed. This new gases then react with molecules in the ozone layer and reduce its layer. Consequently, the result is that there is increase in the average temperature of Earth.
Hence, option 3 is the event most likely to occur due to this solar condition
Answer:
C. increase in the average temperature of Earth
Explanation:
Who is Adolf Hitler?
Answers
Answer: Adolf Hitler created the Nazi Party. He was a dictator and he rose to power when he was the chancellor in 1933 and then Fuhrer in 1934. He was the cause of World War 2 when he had invaded Poland.
*Fuhrer is a German term which means "The Leader".
Answer: Adolf Hitler was a German politician and he made the Nazi Party. He rose to power when he was the chancellor. He was also a dictator and he caused World War 2 when he invaded Poland September 1, 1939.
The number of atoms in 5.78 mol NH4NO3. Show your work.
Answers
Answer:
3.481 x 10²⁴ atoms
Explanation:
Data Given:
Number of moles of NH₄NO₃ = 5.78 mol
Number of atoms of NH₄NO₃ = ?
Solution:
Formula used
no. of moles = no. of atoms / Avogadro's number
As we have to find no. of atoms
So, we have to rearrange the above equation
no. of atoms = no. of moles x Avogadro's number . . . . . (1)
Where
Avogadro's number = 6.022 x 10²³ atoms
Put values in above Equation 1
no. of atoms = 5.78 mol x 6.022 x 10²³ atoms/mol
no. of atoms = 3.481 x 10²⁴ mol
So,
no. of atoms in 5.78 mole NH₄NO₃ = 3.481 x 10²⁴ atoms
Answer:
The answer is 3.48 × 10²⁴
Explanation:
Avogadro's constant/number is used to get the actual number of particles (atoms or ions) in a molecule of a substance.
Avogadro's number is 6.022 × 10²³
To get the actual number of atoms in a substance: avogadro's constant is multiplied by the number of moles of the substance
Hence,
number of atoms = 5.78 × 6.022 × 10²³
number of atoms in 5.78 moles of NH₄NO₃ = 3.48 × 10²⁴
The volume, in liters, of 835 g SO3 at STP. Show your work.
Answers
Answer:
233.856 L
Explanation:
The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
So first of all you should know the amount of moles that represents 835 g of SO₃. For that, you know that:
- S: 32 g/mole
- O: 16 g/mol
So: SO₃= 32 g/mol + 3*16 g/mol= 80 g/mol
Now a rule of three applies as follows: if 80 g of SO₃ are contained in 1 mol, 835 g of the compound, how many moles are there?
moles= 10.44
Finally, you apply a new rule of three as follows: if, according to STP, 1 mole occupies a volume of 22.4 L, 10.44 moles, how much volume does it occupy?
volume=
volume=233.856 L
The volume of 835 g SO₃ at STP is 233.856 L
NEED HELP QUICKLY!!!!! Calculate the volume of each of the following gases at STP. Show your work. A. 7.6 mol Ar
B. 0.44 mol C2H6
C. 3.6 mol NH3
Answers
Answer:
A. 170.24 dm³
B. 9.9 dm³
C. 80.6 dm³
Explanation:
Data Given:
no. of moles of Ar = 7.6 mol
no. of moles of C₂H₆ = 0.44 mol
no. of moles of NH₃ = 3.6 mol
Volume of each gas at STP = ?
Solution:
To calculate volume of gas at STP (Standard temperature and pressure) formula will be used
no. of moles = volume of gas / molar Volume
Rearrange the above equation:
Volume of gas = no. of moles x molar Volume . . . . . . (1)
where
molar volume at STP = 22.4 dm³/mol
•A. Now to calculate Volume for 7.6 mole Ar
Put value in equation 1
Volume of Ar = 7.6 mol x 22.4 dm³/mol
Volume of Ar = 170.24 dm³
___________
•B. Now to calculate Volume for 0.44 mole C₂H₆
Put value in equation 1
Volume of C₂H₆ = 0.44 mol x 22.4 dm³/mol
Volume of C₂H₆ = 9.9 dm³
___________
•C. Now to calculate Volume for 3.6 mole NH₃
Put value in equation 1
Volume of NH₃ = 3.6 mol x 22.4 dm³/mol
Volume of NH₃ = 80.6 dm³
I NEED HELP ASAP!!! Find the mass of each substance. Show your work. A. 7.00 mil H202
B. 5.60 mol NaOH
Answers
Answer:
A: 238 g
B: 224 g
Explanation:
Data given:
A.
number of moles of H₂O₂ = 7.00 mole
mass of H₂O₂ = ?
B.
number of moles of NaOH = 5.60 mole
mass of NaOH = ?
Solution:
Part A:
Formula will be used
no. of moles = mass in grams / molar mass
As we have to calculate mass of substance
So, rearrange the above equation
mass in grams = no. of moles x molar mass . . . . . . (1)
Molar Mass of H₂O₂ = 2(1) + 2(16)
Molar Mass of H₂O₂ = 2 + 32
Molar Mass of H₂O₂ = 34 g/mol
Put values in equation 1
mass in grams = 7.00 mol x 34 g/mol
mass in grams = 238 g
mass of H₂O₂ = 238 g
_______________________
Part B:
Formula will be used
no. of moles = mass in grams / molar mass
As we have to calculate mass of substance
So, rearrange the above equation
mass in grams = no. of moles x molar mass . . . . . . (1)
Molar Mass of NaOH = 23 + 16 + 1
Molar Mass of NaOH = 40 g/mol
Put values in equation 1
mass in grams = 5.60 mol x 40 g/mol
mass in grams = 224 g
mass of NaOH = 224 g
Order the bond angles of the molecules or ions from smallest to largest: O3+, O3, O3-
Answers
The bond angles of the molecules or ions from smallest to largest:
O3- , O3 , O3+
Explanation:
O3- has the smallest bond angle because the added electron makes two places for electron repulsion as it allocates time on the central O.
O3 has lowering bond angle because at O3 appearance of alone pair over oxygen it will experience contracting so it may cause lowering bond angle.
O3+ has a lower electronegativity so it has a higher bond angle. Electronegativity is the tendency of an atom to attract a shared pair of the electron. so electronegativity decreases than bond angle increase so O3 has higher electronegativity so it has lowering bond angle than O3+.
Answer:
O3+, O3, O3-
Explanation:
O3- has the highest bond angle because it has the highest electro negative value. Increase in electronegativity leads to increase in bond angles so as to minimize interelectronic repulsion between the electrons. Decrease in electronegativity leads to decrease in bond angle because the repulsion is minimized.
In general, the more electronegative an ion is, the larger the bond angle. The more electropositive an ion is, the smaller the bond angle. Hence cations are smaller than anions.
When 17.28 mL of a 0.078 M aqueous solution of Na2SO4 is combined with 11.30 mL of a 0.20 M aqueous solution of NaCl and 7.84 mL of a 0.26 M aqueous solution of KCl, what is the total concentration of Na+ in the combined solution?
Answers
Answer:
[ Na+ ]sln = 0.136 M
Explanation:
- Na2SO4 → 2Na+(aq) + SO42-(aq)
- NaCl → Na+(aq) + Cl-(aq)
- KCl → K+(aq) + Cl-(aq)
∴ mol Na2SO4 = ( 0.01728 L)×(0.078 mol/L) = 1.348 E-3 mol Na2SO4
⇒ mol Na+ = (1.348 E-3 mol Na2SO4)×(2 mol Na+/mol Na2SO4)
⇒ mol Na+ = 2.696 E-3 mol
∴ mol NaCl = (0.01130 L)×(0.20 mol/L) = 2.26 E-3 mol NaCl
⇒ mol Na+ = (2.26 E-3 mol NaCl)×(mol Na+/mol NaCl) = 2.26 E-3 mol Na+
⇒ total moles Na+ = 2.696 E-3 mol + 2.26 E-3 mol = 4.956 E-3 mol Na+
∴ total V sln = 17.28 mL + 11.30 mL + 7.84 mL = 36.42 mL = 0.03642 L sln
⇒ [ Na+ ]sln = (4.956 E-3 mol)/(0.03642 L) = 0.136 M
13. During photosynthesis, carbon dioxide and water combine according to the general equation:
Energy
Carbon Dioxide + Water Sugar + Oxygen
Why is photosynthesis a chemical reaction?
A because new substances are formed
B. because an input of energy is required
C. because the reactants are compounds
D. because the products include an element
Cray, metallic zinc filings were added to a heaker of dilute hydrochloric acid in a fume hond.
Answers
The photosynthesis is a chemical reaction because the reactants are compounds. Hence option C is correct.
What is chemical reaction?
Chemical reaction is defined as a procedure that results in the chemical conversion of one group of chemicals into another. Reactants are substances that are present at the beginning of a chemical reaction. A substance that remains after a chemical reaction is complete is known as a product.
Photosynthesis is defined as the method used by plants, algae, and some microorganisms to produce sugar and oxygen from sunlight, carbon dioxide, and water. It is a process that only happens in plants that contain the chlorophyll, a green pigment used in food preparation. Photosynthesis is primarily used to convert solar energy into chemical energy, which is then stored for use at a later time.
Thus, the photosynthesis is a chemical reaction because the reactants are compounds. Hence option C is correct.
To learn more about chemical reaction, refer to the link below:
brainly.com/question/22817140
#SPJ2
Answer:
C bc it is
Explanation:
C IS GOOD ANSWER
How would you balance the following equation NaOh + H2CO3=Na2CO3+H2O ?
Answers
Answer: put 2 in front of NaOH and 2 also in front of H2O
Explanation: 2NaOH + H2CO3 —> Na2CO3 + 2H2O
A process through which an entire room could be warm by turning on the oven and opening the oven door is A. Radiation
B. Conduction
C. Convection
D. Brownian motion
If you could answer and explain why that is the answer that would be great, if not it’s fine :)
Answers
Radiation is the answer
PLS HELP I'LL MARK BRAINLIEST Where can you find hydrochloric acid in your body? What dose it do
Answers
Explanation:
in stomach we find hydrochloric acid
Answer:
in stomach we find hydrochloric acid...
Explanation:
hydrocholiric acid acidify the foof in our stomach...and this acidic environment activates enzymes like pepsinogen in to pepsin.and also this acidic environment destroys harmful bacteria in your food.
17. When energy changes from one form to another, it is known as: a. energy transfer
b. energy transformation
c. energy exchange
d. energy transmit
Answers
Answer:
Energy transformation
Answer:
the answer is 1 3 and 4
Explanation:
i already took the test
PLEASE HELP!! Which of the following is true about the mass of an object?
It is equal to its weight.
It is proportional to its weight.
It is always more than its weight
It changes at different locations.
Answers
Answer:
The correct answer is "It is proportional to its weight."
Explanation:
Mass is the amount of matter that a body contains. Weight is the action exerted by the force of gravity on the body.
The mass of an object will always be the same, regardless of where it is located, because the amount of matter does not vary. Instead, the weight of the object will vary according to the force of gravity acting on it.
The mass is measured in kilograms (kg) and the weight is measured in newtons (N).
The weight is equal to the product of the object's mass and the value of the local gravitational acceleration:
P = m * g
It can be seen that the weight is proportional to the mass of the object.
Answer:
It is proportional to its weight.
Explanation: