Answer:
32.9%
Explanation:
The mass of water present in the original sample can be calculated by the substraction:
m H₂O = sample mass before heating - sample mass after heatingm H₂O = 8.24 g - 6.20 g = 2.04 gThe percent by mass of water can be calculated with the formula:
Water Mass / Original Sample Mass * 100 %[tex]\frac{2.04}{6.20}[/tex] * 100% = 32.9%Which of the following statements about sidestream smoke is not true?
a. It is the smoke that a smoker inhales from a cigarette.
b. It is dirtier and has a different chemical makeup than mainstream smoke.
c. It is the smoke that people around the smoker inhale.
d. It is the smoke that results from the burning end of a cigarette.
Answer: a
Explanation: the smoker actually exhales the sidestream smoke
true or false
1. resistance provides friction to electron movement
2.high resistance will speed up electron movement
3.a circuit is an open path for electrons to move through
4. in a circuit, electrons move from the low voltage area to the higher
5. in a circuit, the light bulb is called the load
Answer:1
Explanation: friction is showing us how in the past
Question (2) If your car
gets 27.8 miles to the gallon, how many liters of gasoline are necessary to travel 112 km?
This problem can be solved in short steps or in one longer step. In either case, please show your work.
Use the following conversion factors:
1 mi = 1.609 km
1 gal = 3.785 L
Answer:
9.48 L.
Explanation:
Hello!
In this case, as the problem mentions a long way to solve it, we are going to apply it because it can provide the answer more rapidly; thus, considering that 112 km are required, 1 mile equals 1.609 km and 1 gallon equals 3.785 liters, we can set up the proportional factor as shown below:
[tex]112km*\frac{1mi}{1.609 km}*\frac{1gal}{27.8mi}*\frac{3.785L}{1gal}[/tex]
Whereas km, mi and gal are cancelled out as it turns out in L; therefore the required liters are:
[tex]9.48L[/tex]
Best regards!
30 POINTS HELPP PLEASE
1: selective breeding
2:traits
3: crop species
4: domestic
5: diverse
6: artificial
7: uniform
in your opinion if the answer is correct please like n mark MI s brain list
what is this element
Answer:
Oxygen
Explanation:
From the question given above, the following data were obtained:
Number of electrons = 8
Number of protons = 8
Number of Neutrons = 8
Name of element =?
Next, we shall determine the atomic number of the element. This can be obtained as follow:
The atomic number of an element is simply defined as the number of protons in the atom of the element. Mathematically, it is expressed as:
Atomic number = proton number
From the question given above,
Number of protons = 8
Therefore,
Atomic number = 8
Comparing the atomic number of the element (i.e 8) with those in the periodic table, we can conclude that the element is oxygen since no two elements have the same atomic number.
Useful:
Harmful:
2. Give an example of how Bacteria can be useful and harmful to man.
Answer:
normal flora useful
Explanation:
protect the skin
yo please help. There is an image PLEASE... HELP... MEEEEE
Answer:
9. B different sounds the dog is exposed to
10. control, dependent, control, control, independent
Explanation:
I NEED THIS TODAY, PLEASE HELP.
Write the following elements in decreasing ionic size. Li+, C4+, F-, O2-
70 POINTS
Answer:
Li+, C4+, O2-, and then F- They're written in decreasing ionic size.
Explanation:
Ionic size means the same thing as ionic radius. Furthermore, Ionic radius is the distance away from the central atom. Ionic radius increases going from top to bottom and decreases across the periodic table.
Lithium is in the 1st family/group with a charge of +1. So it has the biggest ionic radius.
Carbon is in the 4th family/group with a charge of +4. So it has a smaller ionic radius than Lithium.
Oxygen is in the 6th family/group with a charge of -2. So it has a smaller ionic radius than Carbon.
Lastly, Fluorine is in the 7th family/group with a charge of -1. So it has a smaller ionic radius than Oxygen.
question: convert 22.63 miles of oxygen to volume
very urgent
Answer:
506.912 L
Explanation:
From the question given above, the following data were obtained:
Number of mole of O₂ = 22.63 moles
Volume of O₂ =?
Recall:
1 mole of a gas occupy 22.4 L at STP.
With the above information, we obtained the volume occupied by 22.63 moles of O₂ as follow:
1 mole of O₂ occupied 22.4 L at STP.
Therefore, 22.63 moles of O₂ will occupy = 22.63 × 22.4 = 506.912 L at STP.
Thus, 22.63 moles of O₂ is equivalent to 506.912 L.
How many moles are in 99.5 grams of titanium? Round your answer to the nearest hundredth. Be sure to include units.
Answer:
1000
Explanation:
I NEED HELP. This is about science
Answer:
independent varible
Explanation:
The the balanced equations to: solutions of lithium sulfate and potassium phosphate are mixed together to make lithium phosphate and potassium sulfate
Answer:
[tex]3Li_2SO_4+2K_3PO_4\rightarrow 2Li_3PO_4+3K_2SO_4[/tex]
Explanation:
Hello!
In this case, when lithium sulfate and potassium phosphate solutions are mixed to yield lithium phosphate and potassium sulfate, the following chemical equation comes up:
[tex]Li_2SO_4+K_3PO_4\rightarrow Li_3PO_4+K_2SO_4[/tex]
However, as atoms are not balanced we apply the inspection method to obtain:
[tex]3Li_2SO_4+2K_3PO_4\rightarrow 2Li_3PO_4+3K_2SO_4[/tex]
Best regards!
Give me 10 examples of entropy.
Answer:
A campfire is an example of entropy. The solid wood burns and becomes ash, smoke and gases, all of which spread energy outwards more easily than the solid fuel. Ice melting, salt or sugar dissolving, making popcorn and boiling water for tea are processes with increasing entropy in your kitchen.
Explanation:
If this helped you, the please mark me the brainliest.
prove that PV = nRT.
Find your answer in the explanation below.
Explanation:
PV = nRT is called the ideal gas equation and its a combination of 3 laws; Charles' law, Boyle's law and Avogadro's law.
According to Boyle's law, at constant temperature, the volume of a gas is inversely proportional to the pressure. i.e V = 1/P
From, Charles' law, we have that volume is directly proportional to the absolute temperature of the gas at constant pressure. i.e V = T
Avogadro's law finally states that equal volume of all gases at the same temperature and pressure contain the same number of molecules. i.e V = n
Combining the 3 Laws together i.e equating volume in all 3 laws, we have
V = nT/P,
V = constant nT/P
(constant = general gas constant = R)
V = RnT/P
by bringing P to the LHS, we have,
PV = nRT.
Q.E.D
Not all elements readily fit in the metal or non metal groupings. These elements are called metalloids. Examine the table below and classify W, X and Y as metals, metalloids or non-metals.
W= Lustre: Moderately high
Electrical conductivity: Low
Density: Medium
Melting point: Very high
X= Lustre: Low
Electrical conductivity: Nil
Density: Low
Melting point: Low
Y= Lustre: High
Electrical conductivity: High
Density: High
Melting point: High
What's the charge on Ni in the compound NiCi3? *
+1
+2.
+3
- 7
-2.
3
you can't tell
Answer:
+3
Explanation:
Chlorine is anion with a -1 charge. But they are three chlorine atoms.
-1 * 3 = -3
So they have a -3 charge.
So to balance the compound, the nickel has to be a cation with a +3 charge.
-3 + 3 = 0
Furthermore, a chemical bond always has a 0 charge. Remember that.
Hope it helped! Rate my answer a 5 star if correct.
How many moles of Ca are in 1.25x1023 atoms?
We used two conversion factors in this unit, they are provided below. It is your responsibility to know which conversion factor to use!
Avogadro’s number: 6.02x1023 atoms = 1 mole
Molar mass of calcium: 40.078 g Ca = 1 mol Ca
A. 3.12x10^21 mol
B. 0.21 mol
C. 3.12 mol
D. 0.21x10^21 mol
B. 0.21 mol
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
1.25 × 10²³ atoms Ca
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 1.25 \cdot 10^{23} \ atoms \ Ca(\frac{1 \ mol \ Ca}{6.022 \cdot 10^{23} \ atoms \ Ca})[/tex]Multiply: [tex]\displaystyle 0.207572 \ mol \ Ca[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
0.207572 mol Ca ≈ 0.208 mol Ca
If 2.35 L hydrogen gas react with nitrogen gas to form nitrogen trihydride, how many grams of nitrogen will be needed for the reaction to be completed?
0.98 g
0.49 g
21.93 g
1.47 g
Answer:
1.47 g
Explanation:
I promise it's easy points
Describe the life cycle of a star what determines the path a star could take.
help put them in order
Answer:
hello
Explanation:
hi
Which of the following statements about tobacco use is not true?
a. Nicotine narrows blood vessels and puts added strain on the heart.
b. Smoking improves athletic performance.
c. Smoking can wreck lungs.
d. Nicotine in smokeless tobacco is addictive.
Explanation:
b and c statements are not true
if it helps you then plzz mark me brainliest
Answer:
B.) Smoking improves Athletic performance
Explanation:
What is the term used to describe a phase change from liquid to solid?
When a liquid changes into a solid, it is called solidification. When a gas changes into a solid, it is called deposition . When a liquid changes into gas, it is called evaporation. Phase changes are usually caused by changes in temperature or pressure.
Calculate the density (in grams per milliliter) of the following gas at 97 °C and 755 mm Hg Sulfur dioxide (SO2)
Answer:
Density = 2.09×10⁻³ g/mL
Explanation:
We solve this problem from the Ideal Gases Law.
P . V = n . R . T
We know that in STP conditions 1 mol of any gas occupies 22.4 L. So we can compare both situations.
22.4 L = 22400 mL
(P₁ . V₁) / T₁ = (P₂ . V₂) / T₂
We make some conversions:
97°C + 273 = 370 K
755 mmHg . 1 atm / 760mmHg = 0.993 atm
We replace data: (1 atm . 22400 mL) / 273 K = (0.993 atm . V₂) / 370 K
((1 atm . 22400 mL) / 273 K) . 370K = 0.993 atm . V₂
V₂ = 30359 atm . mL / 0.993 atm → 30573 mL
Under those conditions (97 °C and 755 mm Hg) 1 mol of gas is contained in 30573 mL.
We determine the amount of gas: 1 mol of SO₂ weighs 64.06g
Density = m/V → 64.06 g / 30573 mL = 2.09×10⁻³ g/mL
What is exfoliation?
Answer:
Exfoliation involves the removal of the oldest dead skin cells on the skin's outermost surface. Exfoliation is involved in all facials, during microdermabrasion or chemical peels. Exfoliation can be achieved by mechanical or chemical means.
Explanation:
I did copy off internet!
:P
Explain oscillation
Pls help ty!
Answer:regular variation in magnitude or position around a central point. Or movement back and forth at a regular speed
Explanation:
Answer:
movement back and forth at a regular speed
Explanation:
they be oscillatin
The mass of one gallon of water is approximately 3.78 kg or 3780 grams. How many moles are contained in one gallon of water?
a. 102
b. 210
c. 120
d. 201
Answer:
Number of moles of water = 210 mol
Explanation:
Given data:
Mass of water = 3780 g
Number of moles of water = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of water = 18 g/mol
Number of moles = 3780 g/ 18 g/mol
Number of moles of water = 210 mol
pLeeease help im so tired and i need to SLEEP. Answer the 1s you know
1. How does the mechanical energy of a ball that is starting to fall compare to its total energy just before it hits the floor?
2. When you stand in sunlight, what form of energy is emitted by the sun?
3. An eye doctor wants to design reading glasses that also function as sunglasses. Should the eye doctor use a reflective-transparent material or a reflective-opaque material for the lenses? Support your claim.
can someone help I don't understand how to find the amount for the name.
Answer:
A) 6.023*10^23
B)6.023*10^22
Explanation:
AVAGADRO it would take nearly 1 mole of chalk so
1 mole of any substance contain 6.023*10^23 particles.
AVAGADRO it would take nearly 1 mole of ink to print so
1 mole of any substance contain 6.023*10^23 particles.
HELP PLEASE! Which of these is an example of the climate of a region?
Continental
Foggy
Overcast
Sunny
Answer:
Continential
Explanation:
foggy, overcast, and sunny are all examples of weather
2. Which number is not a coefficient in the equation,
2C6H14+ 19O2,-- 12CO2,+ 14H2O?
Answer:
2, 19, 12 and 14 are the coefficients.