Answer:
The particals in a physical change alwayd stay the same, but for a chemical change that is the only time they will change. Not during a physical change
Explanation:
Which waves have more energy than visible light? select all that apply.
a. gamma rays
b. radio waves
c. x-rays
d. ultraviolet waves
e. microwaves
f. infared waves
Answer:
a, c, and d
Explanation:
Gamma rays, x-rays, an ultraviolet (UV) waves have more energy than visible light.
Answer:
Gamma rays, X - rays and ultraviolet ray
Explanation:
High energy waves have high frequency
Calculate the molarity of 0.5 moles NaHCO3 in 3,691 of solutions
Answer: 0.135 M
Explanation:
Hello!
Could you help me solve these exercises?
I want to understand the problems.
I am not the best in chemistry but I am trying to work and understand the subject.
Tank you in advance
Answer:
sorry but can i get the question? cause it is not there
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
1.
Newton's first law of inertia says that an object at rest will stay
at rest and an object in motion will stay in motion unless acted on by a force.
Explanation:
Neo mixes 600ml of black paint with white paint in order to get a gray paint. he think the colour came out too dark ,so that decreases the amount of black paint in the ratio 7:12. Calculate how much black paint it would be
Answer:true
Explanation:
because its just true
it takes 83.0mL of a 0.450 M naOH solution to neutralize 235 mL of an HCl solution. What is the concentration of the HCl solution.
Answer:
0.159 M (3 s.f.)
Explanation:
This is an acid- base reaction, which is also known as a neutralisation reaction.
[tex]\boxed{acid \: + base→salt \: + water}[/tex]
1) Write out the balanced chemical equation.
NaOH (aq) +HCl (aq) → NaCl (aq) +H₂O(l)
The equation is balanced as on each side of the equation, there is 1 Na atom, 1 O atom, 2 H atoms and 1 Cl atom.
2) Find the number of moles of NaOH.
The symbol 'M' denotes Molarity, which is the number of moles per litre.
From the given concentration of NaOH,
1 L NaOH ----- 0.450 mol NaOH
Convert 83.0mL to litres:
Volume of NaOH
= 83 ÷1000
= 0.083 L
Moles of NaOH
= 0.083 ×0.450
= 0.03735 mol
3) Find the number of moles of HCl.
From the balanced equation, 1 mole of HCl is needed to neutralize 1 mole of NaOH.
Thus, amount of HCl
= 0.03735 mol
4) Calculate the concentration of HCl
Concentration= mol/ volume
Converting the volume from mL to L,
235 mL= 0.235 L
Concentration of HCl
= 0.03735 ÷0.235
= 0.15894 mol/L (5 s.f.)
= 0.159 M (3 s.f.)
Determine the calories(same as kilocalories) in a meal consisting of a hamburger with a bun (2760 kJ), french fries (1257 kJ), and a small soft drink (419 kJ). Use significant figures
Answer:
I dont km now this one at all sorry
Find the weight of sodium hydroxide needed to form a 1M solution of 500 mL.
[tex]\\ \rm\Rrightarrow Molarity=\dfrac{Moles\:of\:solute}{Volume\:of\: solution \:in\:L}[/tex]
[tex]\\ \rm\Rrightarrow 1=\dfrac{n}{0.5}[/tex]
[tex]\\ \rm\Rrightarrow n=0.5mol[/tex]
Molar mass of NaOH=23+16+1=40u[tex]\\ \rm\Rrightarrow n=\dfrac{Given\:mass}{Molar\:mass}[/tex]
[tex]\\ \rm\Rrightarrow 0.5=\dfrac{Given\:mass}{40}[/tex]
[tex]\\ \rm\Rrightarrow Given\:mass=40(0.5)=20g[/tex]
hello everyone, i need resources to help for my chemistry test, if you have any free sources for studying: mole conversions, stoichiometry, thermochemistry, reaction types, molar mass, hess' law and chemical equations. That would be nice cuz im studying last minute. Thank you.
Answer:
Yes, there are some free resource like quiz..let quizzes to help guide you through your studying, so if you want just post the questions and I can answer them as well.
Use a table of ka or kb values to determine whether k c for the following reaction is less than, equal to or greater than 1 ch3co2- hso4- ⇌ ch3co2h so42-
Based on the Ka and Kb values of the reactants, the Kc value of the given reaction is greater than 1.
What are the Ka and Kb values of the reactants?The acid dissociation constant, Ka, of HSO4- is 1.2 × 10^-2.
The base dissociation constant, Kb for CH3CO2- is 5.6 × 10^-10
The given equation of reaction is as follows:
CH3CO2- + HSO4- ⇌ CH3CO2H + SO4^2-The Kc of the equation = Ka/KbSubstituting the Ka and Kb values:
Kc = 1.2 × 10^-2/5.6 × 10^-10
Kc = 2.14 × 10^7
Therefore, the Kc value of the given reaction is greater than 1.
Learn more about Ka, Kb and Kc at: https://brainly.com/question/10608589
The bottom wave has a greater _____
Answer:
frequency because it moves up and down faster.
Explanation:
Answer: current and pull making quicker wave and smaller
Explanation:
How many moles of oxygen atoms are in 1.2x10^25 diphosphorus pentoxide molecules
Answer:
19.9 atoms
Explanation:
Grams --- Moles --- Atoms
You're converting from atoms (molecules) to moles.
You do not have to calculate the mass of "di phosphorus pentoxide."
Since you're already given 1.2x10^25 atoms, you start with that. You need to cancel out the atoms, so you need Avogadro's number as shown in the image.
(This has nothing to do with the problem) But in case if you're wondering, the "di" in phosphorus means there's 2 phosphorus and the "pent" means that there are 5 oxygens. So P2O5. Go to your periodic table, multiply their respective atomic masses. You would multiply phosphorus twice and oxygen 5 times. And add them up to get the overall mass.
I hope this helped!
Explain anaerobic respiration with yeast in your own words
Answer:
Is breaking down of food substances in the abscence of Oxygen
A chemist has 2. 0 mol of methanol (CH3OH). The molar mass of methanol is 32. 0 g/mol. What is the mass, in grams, of the sample? 16 grams 30 grams 32 grams 64 grams.
The mass, in grams, of the sample of methanol (CH₃OH) is 64 grams.
How we calculate mass from moles?Mass of any substance can be calculated by using moles as:
n = W/M, where
W = required mass
M = molar mass
In the question that:
Moles of methanol = 2mole
Molar mass of methanol = 32g/mole
On putting these values in the above equation, we get
W = n × M
W = 2mole × 32g/mole = 64g
Hence, 64 grams is the mass of the sample.
To know more about moles, visit the below link:
https://brainly.com/question/15374113
One of these compounds has resonance forms. Draw their Lewis structures to determine which
compound must be represented with resonance forms. Please use the periodic table if needed.
C2H2
O resonance
O no resonance
The molecule C2H2 has resonance structures because it can be represented using four Lewis structures.
What is a resonance structure?Sometimes, a single Lewis struture does not suffice in eliucidation of the bonding properties of a molecule. In such cases, we have to invoke multiple structures called resonace structures.
The resonance structures of C2H2 are shown in the image attached. Hence we can see that the molecule can be represented using four Lewis structures.
Learn more about Lewis structures: https://brainly.com/question/4144781
Answer:
No resonance!
Explanation:
just did the activity <3
The molar mass of hydrogen (H2) is 2. 02 g/mol. A sample contains 4. 00 mol of H2. What is the mass, in grams, of this sample? 1. 98 grams 2. 02 grams 4. 00 grams 8. 08 grams.
Answer:
8.08 G/mol
Explanation:
This is because a mole just equals 1 amount of something. Example, 1 mol of carbon is about 12 AMU. To convert from Mols to Grams, you need to multiply the substance mass by the amount of mols, this case 2.02g/mol by 4.
Hope this helps!
What happens to energy when a bat hits a ball?
the ball starts moving
the energy changes form
kinetic energy moves from the bat to the ball
the total energy increases when the ball moves
HELP
Answer:
the ball starts moving
the energy changes
Five important things about Fluorine>
Answer
here hope this helps !
True or False: High levels of carbon monoxide must be present for a victim to become disoriented and lose consciousness.
you and a friend each hold one end of a long spring toy and shake it back and forth to make waves. What is the medium fot these waves? A:Your friends hand
B:The air C:The spring D:Your hand
Which of the following factors is needed during light-dependent reactions to create ATP and NADPH energy molecules?
Oxygen
Solar energy
Carbon dioxide
Water
Provide an example of an Energy Conversion
Answer:
An example of this is gasoline being put into our cars. With the help of the battery's energy, cause mechanical energy for the car to move faster amd longer than it would have lasted withut gas.
Explanation:
14 Water falling from the sky as
rain or sleet is called
A water cycle
B precipitation
C snow
D hail
Pls help
Answer:
b precipitation
Explanation:
When rain or sleet falls, it is concidered precipitation!
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What happens to the energy absorbed during an endothermic reaction
Answer:
more energy is absorbed when the bonds in the reactants are broken
the name for a wavelength that is formed
from combined waves??
The answer is longitudinal waves
If I gave you 3 moles of methane, how many moles of water will be produced?
Answer: 6 moles
Explanation:
What is difference between atom and element
Answer:
Atom is the part of an element
Explanation:
A particular element is composed of only one type of atom
Last night you were watching the news on the television and the weather forecast for today is muggy and hot. The temperature in the house is rising you turn on the air condition unit and made the room temperature lower.
Answer:
The weather from the outside has impact n what goes on inside. Due to it being hot and muggy out, the weather was able to mess with the temperature in the house.
Explanation:
An air condition is used to regulate the temperature of a room by removing heat as well as reducing humidity.
What is temperature?Temperature is the degree of coldness or hotness of an object or a particular place.
The temperature of an area is affected by the climate and the amount of sunshine.
Also due to heating, water vapor rises into the atmosphere resulting in humidity.
An air condition makes a temperature room cooler by removing heat as well as reducing humidity.
Learn more about temperature and humidity at: https://brainly.com/question/8501238
Which one of the following indicators would be best to use when titrating 0. 1M morphine (Kb = 1. 6 × 10-6) with 0. 3M HCl?
When there is 1M morphine (Kb = 1. 6 × 10-6) with 0. 3M HCl, and the pH mathematically given as
pH=4
The indicator is Methyl red
What is best for titrating 0. 1M morphine (Kb = 1. 6 × 10-6) with 0. 3M HCl?Generally, the equation for the Chemical Reaction is mathematically given as
HCl +BOH--->BCl+H20
Therefore
pH=0.5(pkw-pkb-logl)
pH=0.5()14-5.8-logl
pH=4
In conclusion, The best indicator should have pKa =pH
Hence
Methyl red is best
Read more about Chemical Reaction
https://brainly.com/question/11231920
The best indicator to use when titrating 0. 1M morphine (Kb = 1. 6 × 10-6) with 0. 3M HCl is methyl orange.
What is an acid-base indicator?An acid-base indicator is a substance which change colour or develop turbidity at a particular pH.
Acid-base indicators are used during acid-base titrations to detect when neutralization has occured.
The indicators to be used when combining acid and base are as follows:
Strong acid-strong base - PhenolphthaleinWeak acid-strong base - PhenolphthaleinStrong acid-weak base - Methyl orangeMorphine is a weak base while hydrochloric acid is a strong acid.
Therefore, the best indicator to use when titrating 0. 1M morphine (Kb = 1. 6 × 10-6) with 0. 3M HCl is methyl orange.
Learn more about indicators at: https://brainly.com/question/10563917
Given the chemical formula, KNO3, the percent nitrogen in the compound
Answer:
16 % is the percentage of nitrogen
how many grams of He gas are in 31.35 L of He gas at STP?
Answer:
Ans: 5.8g
Explanation:
31.35L * 1mol/22.4L * 4.00g/1mol = 5.81g