Answer:
A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and formula. (i) It must refer to an actual chemical reaction. (ii) It should be molecular. For example, H, O, N should be written as H2, O2, N2. (iii) It should be balanced and conform to the law of conservation of matter.A chemical equation conveys both qualitative and quantitative information. Qualitatively, a chemical equation tells the names of the various reactants and the products.
which two groups of the periodic table contain the most chemically reactive metals?
Answer:
group 3 and 12 alkali and alkaline earth metal
Which statement below describes the behavior of a Molecules when a substance changes from a gas to liquid
Answer:
As a substance changes from a solid to a liquid to a gas, its molecules first the molecules are moving fast enough, they are able to "escape." They leave the surface of the liquid as gas molecules. Evaporation is not the only process that can change a substance from a liquid to a gas. The same change can occur through boiling.
Explanation:
hopfully this helps!
Most weak bases are:
a. Anions of weak acids
b. Anions of strong acids
C.Cations of weak acids
d. Both A and C
Answer:
The conjugate base of a very weak acid is stronger than the conjugate base of a strong acid.
Explanation:
The stronger the acid, the weaker its conjugate base and vice versa A very weak acid has a very strong conjugate base.
A nuclear _ is a large chamber where fuel rods are located
The answer is going to be a nuclear reactor
what should you do if your bunsen burner does not light after a few tries with the striker?
how to tell if something is a strong or weak acid or base
Answer:
It basically depends upon the pH value of that acid or Base. That's how you can determine whether the substance is a strong or weak acid/base. We have a pH scale ranging from 1 to 14, where 7 is the neutral point. Any substance having a pH of 7 means it is neither an acid nor a Base, but neutral in nature, such as water([tex]H_{2}O[/tex]). Now, if the pH is less than 7, the substance is an acid, similarly if the pH is more than 7, it is a base. As the pH DECREASES, the substance becomes more acidic, on the other hand as the pH INCREASES, the substance becomes more basic. This way you can compare between pH values of two substances and tell which one is stronger or weaker.
For Acids:
If a substance's pH is between 1 and 7 it is an acid. If it is more towards 1, it's a strong acid and if it's more towards 7 it is a weak acid.
For Bases:
If a substance's pH is between 7 and 14 it is a base. If it is more towards 14, it's a strong base and if it's more towards 7 it is a weak base.
Hope that helps...
What are some examples of a physical change? (list more than 2 examples)
Explain two ways to restore the Florida Panther population.
Answer:
Explanation: encourage your legislators to support land acquisition programs such as Florida Forever and the Rural and Family Lands Protection Program.
30g of glucose and 20 g common salt is dissolved in 500 mL of water to make solution. Calculate the concentration of a (a) glucose and (b) common salt in terms of mass by mass percentage of the solution. (Density of water = 1 g/mL)
Answer:
The answer of a is 5.45% and b is 3.64%
Explanation:
Density of water = 1 g/mL
∴ Mass of water (solvent) = 500 g
Mass of solute (glucose) = 30 g
Mass of solute (common salt) = 20g
Mass of solution = (30 + 20 + 500) g = 550 g
a.)Mass percentage of solution for glucose
= Mass of solute (gucose)/Mass of solution × 100
= 30/550 x 100
= 5.45 %
b.)Mass percentage of solution for common salt
= Mass of solute (common salt)/Mass of solution × 100
= 20/550 × 100
= 3.64 %
Thus, The answer of a is 5.45% and b is 3.64%
-TheUnknownScientist 72
Answer:
5.45%
and
3.64%
hope it's helpful
When potential energy is converted into kinetic energy, some of that energy is always in the form of:
А.
light energy
B.
chemical energy
с
nuclear energy
D
heat energy
I need to right a journal entry for school but i don't know what to put Write a journal entry from the perspective of a particle of light,
called a photon. Your story should follow the photon as it
travels from a star in the Milky Way that is 25 light years away
from Earth, all the way to the eye of a young person gazing up
at the night sky through their bedroom window. Compose your
entry in complete sentences.
it is for my 5 grad sicenc
Answer:
here you go
Explanation:
someone help me on this but i still got a hundred
If you were an astrobiologist, what would you do to search for life?
Astrobiologist means someone who studies the possibilities of life beyond earth. what would YOU do to search for life? They're asking for your opinion :)
What is meant by collision theory?
Answer:
The collision theory states that a chemical reaction can only occur between particles when they collide (hit each other).
hope it helps~
Complex organisms require a large number of cells that
A.Complex organisms require a large number of cells that
HELP ME PLZZZ
SMNSNSNS
D
D
D
D
D
D
D
D
D
D
Answer:
#1 is C, #2 is D, #3 is A
Explanation:
Which of the following compounds will have the highest boiling point?
MgCl2
CO2
C12H22O12
,
H2O
explain why almunium is often used for long distance over head electric cables (high voltage)
Answer:
because it does not cost much and can be found easily. due to their low resistance and excellent conductivity.
Explanation:
What is the formula for the binary ionic compound formed between
zinc and nitrogen.
Answer: Zinc nitride (Zn3N2) is an inorganic compound of zinc and nitrogen, usually obtained as (blue)grey crystals. It is a semiconductor. In pure form, it has the anti-bixbyite structure.
Chemical formula: Zn3N2
Space group: Ia-3, No. 206
EC Number: 215-207-3
Appearance: blue-gray cubic crystals
Explanation:
What does it mean when the
frequency of a wave increases?
A. the amplitude increases
B. the amplitude decreases
C the wavelength becomes shorter
D. the wavelength becomes longer
Answer:
The answer is C
Can you put a brainliest for me
Explanation:
Answer:
the wavelength becomes shorter
Explanation:
frequency increases, the wavelength gets shorter. As the frequency decreases, the wavelength gets longer.
Help with this worksheet please (24pts)
Hope you could get an idea from here.
Doubt clarification - use comment section.
*
Which of the following is a acid
нСІ
NaOH
Naci
KOH
Please help I only have until 11:59 to turn in this assignment and I don’t know what I’m doing
Answer:
The correct answer is option A, that is, HCl.
An acid refers to an ion or molecule possessing the tendency of donating a hydrogen ion or a proton, or alternatively, exhibiting a tendency of producing a covalent bond with a pair of electrons. The aqueous Arrhenius acids exhibit characteristic features that offer a practical illustration of an acid.
The acids can turn blue litmus paper red, can form aqueous solutions with a sour taste, and reacts with bases and some kind of metals to produce salts. One of the general aqueous acids is HCl (hydrochloric acid) that is found in the stomach and stimulates digestive enzymes.
Explanation:
This is my class group-work with my friends but we are stuck on this question.
Explanation:
It has to be C, because Carbon can bond with four other atoms and is like a four-hole wheel.
(Sorry if my elplanation was kinds choppy Oof, helpfully it makes sense?)
What is the purpose of the chemical ammonia (NH3) in hair dyes?
Answer: Ammonia, an alkaline chemical, is used to raise the pH level (it's levels of acidity) of our hair during the colouring process. This then lifts the cuticles of the hair fibre and allows the colour to be deposited onto the cortex (the inner part of the hair protected by the cuticles). In hair coloring products, ammonium hydroxide is used to support the lightening action of hydrogen peroxide and to prepare hair to accept color pigments. Alkaline properties of ammonia raise the cuticle and allow peroxide and dye molecules to penetrate the hair shaft. (creds to the internet)
Explanation: Hope this helps! :D
determine the number of grams in 4.87 x 10^22 atoms of barium hydroxide Ba(OH)2'
(fence post model)
Answer:
hola espero que mi respuesta ayude
Explanation:
The concentration of hydroxide ion (-OH) in 1.37 x10^-5 m solution of Ba(OH)2 is calculated as follows
write the equation for dissociation of Ba(OH)2
Ba(OH)2 = Ba^2+(aq) + 2OH^-(aq)
by use of mole ratio between Ba(OH)2 to OH^- which is 1:2 the concentration of OH^- = 2x ( 1.37 x10^-5) = 2.74 x10^-5 M
9
Ammonia is manufactured from nitrogen and hydrogen by the Haber process.
N2(g) + 3H2(g)2NH3(g)
What is the percentage yield when 60 kg of ammonia is produced from 60 kg of hydrogen?
A
5.9%
B
17.6%
с
35.3%
D
50.0%
Answer:
B
17.6%
Explanation:
1. Percentage yield = (Actual yield/theoretical yield) x 100
2. You know actual yield of ammonia (60kg) so you need to work out theoretical yield.
3. mols of hydrogen = m/mr = 60,000/2 = 30,000 mols.
4. 3:2 ratio so (30,000/3) x 2 = 20,000 mols of Ammonia.
5. Therefore mass of ammonia = mr x mols = 20,000 x 17 = 340,000 grams
6. So percentage yield is (60,000/340,000) x 100 = 17.6
How are elements arranged on the periodic table?
Question 10 options:
boiling point
atomic mass (# of protons and neutrons)
density
atomic number (# of proton
Answer: They are arranged by atomic number.
Particulate Electrical Forces Unit Test for Connexus, Chemistry A
I've already finished the questions, but im stuck on the written parts 16-18, can anyone give a hand? :(
I’m sorry no one helped you with those questions. But could you please be a doll and give me the answer for the multiple-choice questions 1-15. Pleaseee I’m so desperate.?
(07.05 HC A scientist investigating electrically-charged objects has decided to test if the number of times you rub a cloth against a balloon increases the amount of time it will stick to the wall. She wrote down her variables in a table. Variable Description Test The numbers of times she rubbed the cloth against the balloon Outcome The length of times the balloon sticks to the wall Control The cloth used in the experiment What would be her hypothesis for this experiment? (2 points) If you stick the balloon to a wall, then it will become electrically charged and stay there for a long period of time If you change the cloth used to change a balloon
Answer: the answer is b
Explanation:I took the test and got it
pls mark as brainliest if correct for you
Determine the amplitude
or period as requested.
Period of y = 4sin 1/3x
a. 4
b. Pi/4
c. 4pi/3
d. 6pi
Answer:I found out that it is c
Explanation:Find an answer to your question Determine the amplitude or period as requested. Period of y = 4sin 1/3x a. 4 b. Pi/4 c. 4pi/3 d. 6pi.
The process in which the nucleus of an atom splits into two lighter atoms, releasing a large amount of energy, is nuclear ______ Fusion Fission Radiation Energy.
Answer:
B. Fission
Explanation:
On edge