Answer:
In acid – base chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. Basic salts contain the conjugate base of a weak acid, so when they dissolve in water, they react with water to yield a solution with pH greater than 7.0.
Explanation:
Hope this helped!
What happens to light waves as they enter the Earth's atmosphere?
Which of the following is the correct formula For aluminum oxide?
A.AIO
B.AI3O2
C.OAI
D.AI2O3
Answer:
The answers D.
Explanation:
Answer:
Its D
Explanation:
Just took the Test.
A gold coin contains 3.47 × 10^23
gold atoms.
What is the mass of the coin in grams?
Answer:
Mass = 114.26 g
Explanation:
Given data:
Number of gold atoms = 3.47×10²³ atoms
Mass in gram = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
3.47×10²³ atoms × 1 mol /6.022 × 10²³ atoms
0.58 mol
Mass of gold:
Mass = number of moles × molar mass
Mass = 0.58 mol × 197 g/mol
Mass = 114.26 g
Please can anyone help me? How are the first 20 elements of the periodic table constructed?
Answer:
Based on the periodic law
Explanation:
All the elements on the periodic table were constructed based on the periodic law.
Henry Moseley in the 1900s re-stated the periodic law by changing the basis of the law from atomic weight to atomic number. The present periodic law is therefore "the properties of elements are a periodic function of their atomic number".
The atomic number is the number of protons in an atom. Based on the graduation of atomic number on the periodic table, elements are classified into groups and periods.it!
t
Calculate How old was the tree when it was
cut down?
Answer:
No numbers how are we supposed to know
Explanation:
A clam farmer has been keeping records of the water temperature and the number of clams developing from fertilized eggs. The data is recorded above.
What is the dependent variable?
What is the independent variable?
What is the optimum temperature for clam development?
Answer:
The dependent variable is the number of clams developing from fertilized eggs.
The independent variable is the water temperature
The optimum temperature for clam development is 30 degrees centigrade.
Explanation:
The graph of the number of clams developing from fertilized eggs and water temperature is attached to this answer.
The independent variable is being manipulated in an experiment. As it changes, it produces a corresponding change in the dependent variable.
Here, the water temperature is the independent variable. As it changes, the number of clams developing from fertilized eggs (dependent variable) also changes alongside.
The optimum temperature is the temperature at which the greatest number of clams developing from fertilized eggs is produced. We can see from the graph that this temperature is 30 degrees centigrade.
Help please! A gas occupies 500 mL at 270 mm Hg and 55°C. If the pressure is changed to 1.8 atm and the temperature is
increased to 100°C, what is the new volume? Be sure to show the setup and the final answer and unit.
Show Your Work
Answer:
V₂ = 112.14 mL
Explanation:
Given data:
Initial volume = 500 mL
Initial pressure = 270 mmHg (270/760 =0.355 atm)
Initial temperature = 55 °C (55 +273 = 328 K)
Final temperature = 100°C (100+273 = 373 K)
Final volume = ?
Final pressure = 1.8 atm
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 0.355 atm × 500mL × 373 K / 328 K × 1.8 atm
V₂ = 66207.5 atm .mL. K / 590.4 K.atm
V₂ = 112.14 mL
5. How many moles are equal to 2.4 x 1023 formula units of sodium chloride?
Answer:
The answer is 0.4 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{2.4 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{2.4}{6.02} \\ = 0.398671096....[/tex]
We have the final answer as
0.4 molesHope this helps you
How many molecules are in 210 grams of CO2?
Answer:
30 molecules
Explanation:
easy
arrange the following in order of increasing mass . a. 16 water molecules b. 2 atoms of lead 3. 5.1*10^-23
. Which of the following statement is FALSE about gas particles? a. Gases expand to fill their container. b. Gases increase in movement when temperature increases Gases are in constant rapid motion. d. Gas particles are packed tightly together. please hurry
Answer:
D
Explanation:
which element is more reactive out of oxygen and sulphur
Answer:
Oxygen
Explanation:
Oxygen is more reactive because it has small atomic size which has high tendency to attract more electrons.
Two individual atoms of the same element are slightly different. One has one more proton than it has electrons. The other has one more electron than it has protons. These atoms are both
ions
isotopes
freons
xenons
phlogistons
Answer:
ions
Explanation:
Individual atoms of the same element but having slightly different number of protons and electrons are called ions.
Ion is a charged particle.
An atom is made up of three fundamental subatomic particles. Protons are the positively charged particles Electrons are the negatively charged particles Neutrons do not carry any charges.When the number of protons > electrons the body is positively charged.
When the number of electrons > protons the body is negatively charged.
Charged particles are called ions.
Conversion factor 1 calorie (kicalorie) = 1000 calories
Answer:correct
Explanation:
The large calorie, food calorie, or kilocalorie (Cal, calorie or kcal) is the amount of heat needed to cause the same increase in one kilogram of water. Thus, 1 kilocalorie (kcal) = 1000 calories (cal).
how many sig figs are in 0.0093
Answer:
there are two significant figures
Explanation:
Answer:
there are two
Explanation:
because the zeros dont count
Plz answer quickly! :))
How are the shapes of covalent compounds made?
Hope this might help a little
Explain how the isotopes and ions of an atom differ.
Answer:
istopes is a situation in which each of two or more forms of same element that contain equal number of proton....while ions of an atoms are with extra electrons or missing electrons so they tends to differ
NEED HELP ASAP!!!!!!!Instructions
Please complete the macromolecule chart using your notes and the PowerPoints. If you have trouble typing directly on the paper remember you probably need to download it first so it opens in a new window. Remember to save it with your name at the end so that I can tell whose paper it is. Than upload and submit. If you are having trouble, let me know.
Answer:
mouse
Explanation:
2.Chromosomes are____
Both A and B
Made of DNA
None of the above
Found in the nucleus of a cell
Answer:
Both A and B
Explanation:
Answer: The answer is the last one: found in the nucleus of a cell
Explanation:
Each chromosome is made of protein and a single molecule of dna. As It is getting passed from the parents to the offspring the dna contains specific instructions that make each type of living thing unique.
Geologic Time Scale
Time Period Duration (Millions of Years Ago)
Cenozoic 66-0
Mesozoic 252-66
Paleozoic 541-252
According to the scale, what time period are we in today?
a
Cenozoic
b
Mesozoic
c
Paleozoic
d
None of these
How do you know when the endpoint is reached in a titration? When does this occur?
Before a titration, indicator is added to the analyte (which is in the flask, and usually the chemical of unknown concentration). The titrant is then placed in a burette and slowly titrated into the analyte. When the indicator changes color is when the endpoint of the titration has been reached. This occurs (approximately) at the equivalence point.
Which is most likely the result of millions of metal atoms crowding together so that molecular orbitals become combined?
Answer:
(The Formation Of Bands In A Crystal)
How many moles are equal to 1.3 x 1024 atoms of aluminum?
Answer:
The answer is 2.16 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{1.3 \times {10}^{24} }{6.02 \times {10}^{23} } \\ = 2.159468...[/tex]
We have the final answer as
2.16 molesHope this helps you
Please help me what is the answer
There are 20.8 moles of propanol
Further explanationThe mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
1.2 x 10⁵ molecules of propanol
[tex]\tt \dfrac{1.25\times 10^{25}}{6.02\times 10^{23}}=20.8~moles[/tex]
What is the correct formula that
would result from the combination
of the two ionic species?
Cs1+ and Ci1-
Answer:
CsCl
Explanation:
The ionic species are:
Cs⁺ and Cl⁻
The two ions will combine to form an ionic compound which results from the electrostatic attraction between oppositely charged ions.
Elements or ions exchange directly their combining powers or their simplest whole number ratio during the formation of chemical formulae of compounds
Cs⁺ and Cl⁻
Combining power 1 1
Exchange of
valencies 1 1
Compound CsCl
wich if the following statements best describes why the mass of a bowling ball would not change if it were transported from earth to the moon?
gravity is constant forge
the bowling ball will adapt to the changes in gravity
matter is resistant and changes gravity
the amount of mattet in the bowling ball remains the same
Answer:
the amount of matter in the bowling ball remains the same
Explanation:
The reason why the mass of the bowling ball on earth and moon remains the same is that matter in the bowling ball remains the same.
Mass of any substance is the amount of matter it contains.
Since there is no loss in matter, the mass of the bowling ball anywhere in the universe will be the same. Only the weight changes due to differences in gravity.20cm3 of hydrochloric acid neutralized 25cm3 0.1moldm-3 sodium trioxocarbonate(IV) solution, find (i) the concentration of hydrochloric acid in moldm-3. (ii) the concentration of hydrochloric acid in gdm-3. (H=1.00, Cl=35.5)The equation for the reaction: 2HCl + Na2 CO3 → 2NaCl + H2O
Answer:
1. 0.25 moldm¯³.
2. 9.125 gdm¯³.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2HCl + Na2CO3 → 2NaCl + H2O + CO2
From the balanced equation,
The mole ratio of the acid, HCl (nA) = 2
The mole ratio of the base, Na2CO3 (nB) = 1
1. Determination of the concentration of the acid, HCl in moldm¯³.
Volume of acid, HCl (Va) = 20 cm³
Volume of base, Na2CO3 (Va) = 25 cm³
Concentration of base, Na2CO3 (Cb) = 0.1 moldm¯³
The mole ratio of the acid, HCl (nA) = 2
The mole ratio of the base, Na2CO3 (nB) = 1
Concentration of acid, HCl (Ca) =?
Cava /CbVb = nA/nB
Ca × 20 / 0.1 × 25 = 2/1
Ca × 20 / 2.5 = 2
Cross multiply
Ca × 20 = 2.5 × 2
Ca × 20 = 5
Divide both side by 20
Ca = 5/20
Ca = 0.25 moldm¯³
Thus, the concentration of the acid, HCl in moldm¯³ is 0.25 moldm¯³
2. Determination of the concentration of the acid, HCl in gdm¯³
Concentration of the acid, HCl = 0.25 moldm¯³
Molar mass of HCl = 1 + 35.5 = 36.5 g/mol
Concentration of the acid, HCl in gdm¯³ =?
Conc. in moldm¯³ = Conc. in gdm¯³ /Molar mass
0.25 = Conc. in gdm¯³ /36.5
Cross multiply
Conc. in gdm¯³ = 0.25 × 36.5
Conc. in gdm¯³ = 9.125 gdm¯³.
which star is the dimmest HELP PLEASE
Answer:
Bellatrix.
Explanation:
Answer:
vega i believe just look at the number and see what kinda is less ykwim
Which of the following is an indication of a physical change?
O A. The formation of a new substance
O B. Giving off a smell
O C. A change in the shape of a substance
O D. The production of gas and heat
Answer:
A change in the shape of a substance
Explanation:
Because when ths shape of a sunstance changes , its physical appearance changes .A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible. The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.
How are elements and compounds a part of our daily lives?
Answer:
Aluminium (A1) -Used in the production of duralumin alloy for use in the construction of aeroplane bodies. 3. Silicon (Si) -To make microchips 4. Sulphur (S) -To make matches, fireworks and for the manufacture of sulphuric acid 5.
Explanation:
Hope this helped!
Answer:
yes
Explanation:
we use different elements and compounds in our life ex salt and iron but most of the substances found in our environment are mixture btw scientists need to classified substances to work with our substances and to study pure substances hope it helps u