Answer:
Conduction
Explanation:
Conduction is the transfer of energy from one molecule to another by direct contact.
in 2 hours a bicyclist traveled 75 kilometers. What was the bicyclist's average speed?
Answer:
37.5 miles per hour....
235
234
2) Uranium is used in nuclear reactors and is a rare element on earth. Uranium has three common
isotopes. If the abundance of U is 0.01%, the abundance of U is 0.71%, and the abundance of
U is 99.28%, what is the average atomic mass of uranium?
238
Answer:
Average atomic mass of uranium = 237.97 amu
Explanation:
Given data:
Abundance of U-234 = 0.01%
Abundance of U-235 = 0.71%
Abundance of U-238 = 99.28%
Average atomic mass of uranium = ?
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass) / 100
Average atomic mass = (234×0.01)+(235×0.71)+(238+99.28) /100
Average atomic mass = 2.34 + 166.85+23628.64 / 100
Average atomic mass = 23797.83 / 100
Average atomic mass = 237.97 amu.
Classify each statement as an observation, a law, or a theory. Drag the appropriate items to their respective bins
Classify each statement as an observation, a law, or a theory.
Drag the appropriate items to their respective bins.:
(A): Neon does not react with sodium at room temperature and pressure.
(B): Chlorine reacts violently with sodium at room temperature and pressure.
(C): If elements are listed in order of increasing mass of their atoms, their chemical reactivity follows a repeating pattern.
(D): The reactivity of elements depends on the arrangement of their electrons.
Observation: (A), (B)
Law: (C)
Theory: (D)
The statement given for law and theory were wrong. But of observation is correct.
From the given data,
Observation:Neon is inert gas.
Chlorine is highly reactive gas.
This can be said that Neon belongs to group 18 which have stable configuration.
While, chloride require one electron to get stable configuration of noble gas. They are electronegative in nature. Therefore, it is highly reactive in nature.
LawIf the element are listed in order of increasing mass of their atom their chemical reactivity follows a repeating pattern.
TheoryThe reactivity of element depends on the arrangements of their electrons.
Thus, we concluded that the statement given for law and theory were wrong.
learn more about electronegativity:
https://brainly.com/question/1600292
#SPJ9
30 points and brainliest for correct answer!!
Examine the Lewis structure.
H-H-O:
What is incorrect in the structure? Check all that
apply.
The middle hydrogen is surrounded by 4
electrons.
Oxygen is surrounded by 8 electrons.
The middle hydrogen is bonded to 2
elements.
There are too many electrons in the final
structure.
Answer:
The middle hydrogen is surrounded by 4 electrons
The middle hydrogen is bonded to 2 elements
There are too many electrons in the final structure
Explanation:
Answer:
A: The middle hydrogen is surrounded by 4 electrons.
C: The middle hydrogen is bonded to 2 elements.
D: There are too many electrons in the final structure.
Explanation:
Renewable energy resources such as wind and
solar energy have an advantage because they
cannot be depleted.
Agree or disagree
Answer:
Agree
Explanation:
Renewable energy resources are advantageous because they cannot be depleted with active usage.
Renewable resources are resources that can replenished easily and quickly as they are being used up in the ecosystem. Solar energy from the sun is inexhaustible and readily available.Non-renewable energy resource cannot be replenished as they are being used in nature.
Such resources must be conserved.
Which are examples of elements? Select all that apply
CO2
C
H2O
Au
What are the most common metric units used in science?
Answer its a
Explanation:
Which best represents the law of conservation of mass?
: 6 ORE
mass of reactants > mass of products
O mass of reactants < mass of products
mass of reactants = mass of products
O mass of reactants mass of products
-
Answer:
D. mass of reactants → mass of productsExplanation:
The only difference between the options are the sign. The sign between the two is an arrow to represent the change.
(I know this because we're learning about it in class and it's an arrow not an equal, greater, or less than sign)
Miguel?? Where are you
Answer:
in the movie ' Coco '.........
How many atoms are in 1.3g C? Answer in Units of Atoms
Answer:Okay, so first, let's turn the grams into moles.
1.3 g C / 12.011 g/mol = 0.1082341187 mol C
Next, we need to multiply it by Avogadro's Number for the number of atoms.
0.1082341187 mol C * 6.022*10^23 mol^-1 = 6.51785863*10^22 atoms C
Now we take significant figures into consideration. We started with two, so we need to end it with two.
6.5*10^22 atoms C
Explanation:
SF2 and CH4 have similar, but not identical bond angles. Explain this observation and explain why they are slightly different.
Answer:
In CH4 bond angle is 109.5 but it is slightly less than 109.5 in SF2 both compounds have same hybridization SP3 but bond angle of SF2 is less due to presence of two lone pairs
Explanation:
Rainfall over land often results in water runoff and infiltration. Explain how runoff differs from infiltration.
Plz help T^T
Answer:
Runoff is water from precipitation that along with the ground level to water bodies while infiltration is water that seeps through into the soil and could possibly become groundwater.
Explanation:
Normally, where there are more cities and capitals and fewer trees, there would be more runoff and flooding would happen more frequently. In the countryside, there would be more trees and roots that would absorb the water from the soil and thus there would be more infiltration.
Christopher berg land holds the world record for most distance run on a treadmill in day. He ran 247.54 km. How many miles per hour did Chris have to run to accomplish this?
note: Can you please explain how to do this and not just give the answer?
Answer:
6.408924056 miles/hour.
Explanation:
First we have to convert 247.54 km to miles. The conversion factor will be 1 km = 0.621371 miles. To do this I set up my stoichiometry.
247.54km | 0.621371miles = 153.8141773 miles
| 1 km
Now we have 153.8141773 miles per 1 day. The conversion factor will be 1 day = 24 hours.
153.8141773 miles | 1 day 6.408924056 miles/hour.
1 day | 24 hours
(if you need to know what I did with the stoichiometry just ask! I'll be happy to help!)
Please help me with this question please.....
Answer:
gain electrons
Explanation:
"atoms gain electrons, they acquire a negative charge "
Using the table below, identify the unknown material that has a mass of 15,06 g and a
volume of 0.78 ml
Substance Density (g/cm) Substance Density (g/cm")
Ice (00 0.917 Human fat 0.94
Water (4.0°C) 1.0000 Cork 0.22-0.26
Gold
19.31
Table sugar 159
Helium (250) 0.000 164 Balsa wood 0.12
Air (250) 0.001 185 Earth 5.54
Ole
Water
Gold
Hellum
O Air
lo
The unknown material : gold
Further explanationDensity is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
ρ = density
m = mass
v = volume
mass of unknown the material : 15.06 g
volume = 0.78 ml
The density :
[tex]\tt \rho=\dfrac{m}{V}\\\\\rho=\dfrac{15.06}{0.78}=19.31~g/ml[/tex]
materials that match the density: gold
Which substance is considered to be neutral on the pH Scale? *
2 points
battery acid
pure water
bleach
ocean water
Answer:
Pure Water
Explanation:
Battery acid is well and acid
Bleach is a base
Ocean water is impure so it could lean either way
a material will float on the surface of a liquid if the material has a density less than that of the liquid. given that the density of water is approximately g/ml, will a block of material having a volume of and weighing lb float or sink when placed in a reservoir of water?
The density of water is approximately 1.0 g/mL. So, the block will float in water because it is less dense than water.
What is density?Density is a scalar quantity. It is calculated as the mass divided by the volume.
The density of water is approximately 1.0 g/mL
The volume of 1.2 x 10^4 in^3
and weighing 350 lb
D = m / v where D is density, m is mass and v is volume
Converting 1.2 x 10⁴ into 10³
1.2 x 10⁴ in ³ (16.39 mL/ 1 in3) = 196,980 mL
Converting 350 lb into grams
350 lb (454 grams/1 lb) = 158,900 grams
D = m / v = 158,900 grams / 196,980 mL
D = 0.807 g/mL
Thus, due to its lower density than water, the block will float in the water.
To learn more about density, refer to the link:
https://brainly.com/question/4223759
#SPJ4
The question is incomplete. Your most probably complete question is given below:
A material will float on the surface of a liquid if the material has a density less than that of the liquid. Given that the density of water is approximately 1.0 g/mL, will a block of material having a volume of 1.2 x 10^4 in^3 and weighing 350 lb float or sink when placed in a reservoir of water?
One difference between molecular formula and molecular weight.
Answer: The formula mass (formula weight) of a molecule is the sum of the atomic weights of the atoms in its empirical formula. The molecular mass (molecular weight) of a molecule is its average mass as calculated by adding together the atomic weights of the atoms in the molecular formula.
Hope this helps.... Stay safe and have a great weekend!!!!! :D
what is meant by valency of an element ? give an example
Answer:
valency of an element is a combining power of an element.
for example oxygen has six valance electron but its valency is 2.
hope it helps.
What is the difference between atomic elements and molecular elements?
how long did it take for a car to travel 20 meters with a speed of 10m/s
Answer:
2 second
Explanation:
yes
what is the mass of 1.20 x 10^25 atoms of He
Answer:
79.7 g He
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
1.20 × 10²⁵ atoms He
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of He - 4.00 g/mol
Step 3: Convert
[tex]1.20 \cdot 10^{25} \ atoms \ He(\frac{1 \ mol \ He}{6.022 \cdot 10^{23} \ atoms \ He} )(\frac{4.00 \ g \ He}{1 \ mol \ He} )[/tex] = 79.7077 g He
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
79.7077 g He ≈ 79.7 g He
PLEASE HELP QUICK Lab - Limiting Reactant and Percent Yield
Data (Trial 1) (5 Points)
Observations during Reaction:
3CuCl2(aq) + 2Al(s) → 3Cu(s) +2AlCl3(aq)
Measured Mass (g)
N/A
N/A
Molar Mass ( )
134.45
26.98
N/A
N/A
Actual Moles (mol)
N/A
N/A
Analysis: The limiting reactant is _ because . . .
Data (Trial 2) (5 Points)
Observations during Reaction:
3CuCl2(aq) + 2Al(s) → 3Cu(s) +2AlCl3(aq)
Measured Mass (g)
Filter paper alone Filter paper + Cu
Cu alone
N/A
Molar Mass ( )
134.45
26.98
63.55
N/A
Actual Moles (mol)
N/A
Analysis: The limiting reactant is _ because . . .
Theoretical yield of copper based on the limiting reactant; (insert the answer from above)
_ _: _ _ moles = _ g
Percent yield: _ _%
Limiting Reactant and Percent Yield - Lab Report
Purpose (5 Points)
Hypothesis (5 Points)
Analysis
(5 Points) If you put a piece of zinc into a solution of copper (I) sulfate and allow the single replacement reaction to go to completion, how will you know which of the reactants is the limiting reactant? Write the balanced equation, including the states of matter of the reactants and products, to help support your answer.
CuSO4(___) + Zn (__) → Cu(__) + ZnSO4 (___)
Is it balanced? __________ If not, fix it.
(5 Points) What is the difference in actual yield and theoretical yield?
Solid Silicon can be reacted with Nitrogen gas at a high temperature to form silicon nitride (Si3N4).
1.20 moles of Silicon are added to 1.00 moles of Nitrogen gas.
(5 Points) Balance the equation and indicate the phases.
Si (___) + N2 (___) → Si3N4 (___)
(5 Points) What is the limiting reactant? You must show your work.
(5 Points) How many moles of silicon nitride will be made? You must show your work.
(5 Points) What is the benefit of having a limiting reactant in a reaction?
(5 Points) In a manufacturing process why would you prefer not to have a limiting reactant?
(5 Points) Can you tell from the masses of the reactants which one of the reactants will be the limiting reactant? Defend your answer (use an equation within your defense).
4.95 g of ethylene (C2H4) are combusted with 3.25 g of oxygen.
(5 Points) Balance the equation. (ethylene plus oxygen yields carbon dioxide and water)
C2H4 + O2 → CO2 + H2O
(5 Points) What is the limiting reactant? You must show your work.
(5 Points) If the actual yield of Carbon dioxide is 2.50 g, what is the percent yield for the reaction? You must show your work.
Silver nitrate reacts with iron (III) chloride to give silver chloride and ferric nitrate. In a particular experiment, it was planned to mix a solution containing 25.0 g of silver nitrate with another solution containing 45.0 grams of iron (III) chloride.
(5 Points) Balance the equation.
AgNO3 + FeCl3 → AgCl + Fe(NO3)3
(5 Points) What is the limiting reactant? You must show your work.
(5 Points) What is the theoretical yield of grams of AgCl that could be obtained? You must show your work.
(10 Points) When 56.6 g of solid calcium and 30.5 g of nitrogen gas undergo a reaction that has a 93.0% yield, what mass of calcium nitride forms? Make sure you balance the equation to help solve the question and show all of your work.
Ca(s) + N2 (g) → Ca3N2 (s)
Answer:
im stuck on it too unfortunatley
Explanation:
If 5.0 g of potassium chlorate (KClO3) is decomposed, what volume of oxygen gas is produced at STP?
Answer:
1.37dm³
Explanation:
To solve this problem, let us write the reaction expression:
2KClO₃ → 2KCl + 3O₂
Now, mass of KClO₃ is 5g, let us find the number of moles;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of KClO₃ = 39 + 35.5 + 3(16) = 122.5g/mol
Now;
Number of moles = [tex]\frac{5}{122.5}[/tex] = 0.04mole
So;
2 moles of KClO₃ will produce 3 moles of oxygen gas
0.04 mole of KClO₃ will produce [tex]\frac{3 x 0.04} {2}[/tex] = 0.06moles
At STP;
1 mole of gas has a volume of 22.4dm³
0.06 mole of oxygen gas will have a volume of 22.4 x 0.06 = 1.37dm³
To verify the law of Conservation of mass in a chemical reaction.
Write the formulae of the following-
a) Magnesium hydroxide
b) Hydrogen sulphide
c) Calcium oxide
d) Barium chloride
e) Sodium carbonate
f) Ammonium sulphate
g) Aluminium oxide
h) Magnesium bicarbonate
i) Aluminium phosphate
j) Silver nitrate
Answer:
To verify the law of Conservation of mass in a chemical reaction.
Write the formulae of the following-
a) Magnesium hydroxide
b) Hydrogen sulphide
c) Calcium oxide
d) Barium chloride
e) Sodium carbonate
f) Ammonium sulphate
g) Aluminium oxide
h) Magnesium bicarbonate
i) Aluminium phosphate
j) Silver nitrate
Kyun-won putts a golf ball 153m. The ball stops rolling after 3 seconds.
Calculate the speed of the ball.
A. 5.1 m/s
B. 5.0 m/s
C. 50 m/s
D. 51 m/s
Answer:
d.51 m/s
Explanation:
51*3=153
Fill in the blank with either atom or molecule. Water is a(n) ____________________.
Answer:
Molecule
Explanation:Water is an molecule.
Answer:
Molecule
Explanation:
water is a Molecule
What happens when a wave hits an object?
the wave is reflected
the wave continues on
the wave is interfered with
the wave stops
Answer:
the wave is reflected. it starts heading towards the other direction
Explanation:
15. What is the wavelength of a 1.32 x 10^-6 eV wave?
The wavelength of a 1.32 x 10-⁶ eV wave is 0.939m or 9.39 × 10⁸nm.
How to calculate wavelength?The wavelength of a wave can be calculated using the following formula:
wavelength = speed ÷ frequency
However, the frequency of the wave needs to be calculated first using the formula as follows:
E = hf
Where;
E = energy of the waveh = Planck's constant (6.626 × 10-³⁴J/s)f = frequency1 electronvolt = 1.602 × 10-19 joule
Hence, 1.32 × 10-⁶ eV is equivalent to 2.11487 × 10-²⁵J.
2.11487 × 10-²⁵J = 6.626 × 10-³⁴ × f
f = 2.11487 × 10-²⁵ ÷ 6.626 × 10-³⁴
f = 3.2 × 10⁸Hz
Wavelength = 3 × 10⁸ ÷ 3.2 × 10⁸
Wavelength = 0.9375 × 10⁰
Wavelength = 0.94m
Therefore, the wavelength of a 1.32 x 10-⁶ eV wave is 0.939m.
Learn more about wavelength at: https://brainly.com/question/13533093
#SPJ1
\identify which reaction is likely to have the greatest positive enthalpy change. p(g) 5cl(g)→pcl5(g) p(g) 3cl(g)→pcl3(g) pcl3(g)→p(g) 3cl(g) pcl5(g)→p(g) 5cl(g)
The greatest positive enthalpy change has PCl₅(g) → P(g) + 5Cl(g)
An enthalpy change is difference between the enthalpy after the chemical reaction has completed.
An enthalpy change of phosphorus(V) chloride (PCl₅) molecule is energy needed for breaking up one molecule of phosphorus(V) chloride into one phosphorus and five chlorine atoms.
In a chemical reaction, chemical bonds are forming and breaking and this cause the transformation of one group of chemical substances to another.
Energy is needed to break chemical bonds in molecules (positive enthalpy change), while during formation of molecule, energy is released (negative enthalpy change)
The stronger are the bonds, more energy is needed and enthalpy change is more positive.
PCl₅ has more bonds to break than PCl₃.
More about enthalpy change: brainly.com/question/16387742
#SPJ4