Three samples of a solid substance composed of elements A and Z were prepared. The first contained 4.31 g A and 7.70 g Z. The second sample was 35.9% A and 64.1% Z. It was observed that 0.718 g A reacted with Z to form 2.00 g of the third sample. Show that these data illustrate the law of definite composition.
Answers
Answer:
The percentage composition of the elements of the compound in the three samples is the same.
Explanation:
The law of definite proportions states that all pure samples of a particular chemical compound contain the same elements in the same proportion by mass.
Sample A:
Mass of A = 4.31 g; mass of Z = 7.70 g
Total mass of sample = 12.01
Percentage mass of A in the sample = (4.31 * 100)/12.01 = 35.9 %
Percentage mass of Z in the sample = (7.70 * 100)/12.01 = 64.1 %
Sample B:
Percentage mass of A in the sample = 35.9 %
Percentage mass of Z in the sample = 64.1 %
Sample C:
Mass of A = 0.718 g; Total mass of sample = 2.00 g
mass of Z = mass of sample - mass of A = 2.00 g - 0.718 g = 1.282 g
Percentage mass of A in the sample = (0.718 * 100)/2.00 = 35.9 %
Percentage mass of Z in the sample = (1.282 * 100)/2.00 = 64.1 %
From the calculations, it can be seen that the percentage composition of the elements in the compound is the same for the three samples.
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How many valence electrons must two atoms share to form a single covalent bond? answers A.2 B.4 C.3 D.1
Use the equation editor or "Insert Chemistry - WIRIS editor" to write the balanced molecular chemical equation for the reaction of aqueous 0.13 M lead (II) nitrate, with 0.19 M potassium carbonate. You may need to consult Appendix E to determine the states of each reactant and product. Assume any insoluble products are completely insoluble.
Which is an example of plasmas in nature? solar cells plasma balls auroras clouds
What is the total number of atoms contained in 2.11 moles of nickel?
Answers
Explanation:
a)Boyle's law states that pressure is inversely proportional to the volume of the gas at constant temperature.
(At constant temperature)
The equation given by this law is:
where,
are initial pressure and volume respectively.
are final pressure and volume respectively.
b) A graph of the relationship is attached as an image.
Which organism gains energy from eating the frog?
Which organism has the most available energy in this food chain?
Answers
Answer:
grass
snake
grass
Explanation:
just did it :)
But, the producers should be on the bottom of the food chain, likely grass or something of the sort (plants)
If the frog has a line pointing to another organism, then that’s the organism that gains energy from eating it
Answers
Given Mass of pure silver (Ag) = 265 mg
Silver chloride AgCl which is used in plating silver contains 75.27 % Ag
This means that:
A 100 mg of silver chloride contains 75.27 mg of silver
Therefore, the amount of silver chloride required to plate a sample containing 265 mg silver would correspond to:
265 mg Ag * 100 mg AgCl/75.27 mg Ag
= 352.1 mg AgCl
Answer:
0.35215 grams of silver chloride required to plate 265 mg of pure silver.
Explanation:
Mass of silver = 265 mg = 0.265 g
Moles of silver =
According to reaction, 2 moles of silver are obtained from 2 moles of silver chloride.
Then 0.002454 moles of silver will be obtained from :
of silver chloride
Mass of 0.002454 moles of silver chloride:
= 0.002454 mol × 143.5 g/mol = 0.35215 g
0.35215 grams of silver chloride required to plate 265 mg of pure silver.
Answers
Taking into account the definition of ionic and covalent bond, the bonds that chlorine forms with sodium (to form NaCl) and with carbon (to form CCl₄) are different in both compounds.
Ionic bond
An ionic bond is a type of chemical bond that occurs when one atom gives up an electron to the other, in order for both to achieve electronic stability.
This union normally occurs between metal and nonmetal elements with different electronegativity, which means that the elements have different capacity to attract electrons.
In other words, an ionic bond is produced between metallic and non-metallic atoms, where electrons are completely transferred from one atom to another. During this process, one atom loses electrons and another one gains them, forming ions. Usually, the metal gives up its electrons forming a cation to the nonmetal element, which forms an anion.
Covalent bond
The covalent bond is the chemical bond between atoms where electrons are shared, forming a molecule. Covalent bonds are established between non-metallic elements, such as hydrogen H, oxygen O and chlorine Cl. These elements have many electrons in their outermost level (valence electrons) and have a tendency to gain electrons to acquire the stability of the electronic structure of noble gas.
Bonds of NaCl and CCl₄
In the case of NaCl, Na is a metal while Cl is a nonmetal. So NaCl is an ionic bond.
On the other hand, in the case of CCl₄ both C and Cl are two non-metallic elements. So CCl₄ is a covalent bond.
In summary, the bonds that chlorine forms with sodium (to form NaCl) and with carbon (to form CCl₄) are different in both compounds.
Learn more about
ionic bond:
brainly.com/question/24755818?referrer=searchResults
brainly.com/question/24776745?referrer=searchResults
covalent bond:
brainly.com/question/24900155?referrer=searchResults
Answer:
No, NaCl is formed by an ionic bond, and CCl4 would be formed by covalent bonds.
Explanation:
NaCl is an ionic bond because of their opposite charges while carbon and chlorine are sharing their electrons making it a covalent bond.
Answers
Due to the conjugate base of the hydrogen atom is aromatic, Hb is regarded as the most acidic. Because the conjugate base of the hydrogen atom Hc is anti-aromatic, it is the least acidic.
The correct options are:
(A) - (a)
(B) - (d)
What are the most and the least acidic hydrogen atom?
The hydrogen connected at the heptatriene's tertiary position (at the 7-methyl) would be particularly acidic, as its removal would leave a positive charge that could be transported around the ring via resonance.
The hydrogen connected to the pentadiene (5-methyl) at the tertiary position would not be acidic, as removing it would result in an anti-aromatic structure.
Thus, the least acidic H atom is Hc and the most acidic H atom is Hb.
Learn more about hydrogen atom, here:
The hydrogen that is attached at the tertiary position on the heptatriene (at the 7-methyl) would be very acidic, as removal would leave a positive charge that could be moved throughout the ring through resonance. This would mean that the three double bonds would be participating in resonance, and the deprotonated structure would be aromatic, thus making this favorable.
The hydrogen that is attached at the tertiary position on the pentadiene (5-methyl) would NOT be acidic, as removal would cause an antiaromatic structure.
Any other hydrogens would NOT be acidic. Those vinylic to their respective double bonds would seriously destabilize the double bond if removed, and hydrogens attached to the methyl group jutting off the ring have no incentive to leave the carbon.
Hope this helps!
1) K+ and H+ and PO43-
6
2) K 2+ H+, and PO43-
9
3) K+, H+, p3-, and O2-
4) K2H3+ and PO43-
5) K2HPO4 is not ionic.
Answers
Answer:
K⁺ and HPO₄²⁻ ions are present in K₂HPO₄
Explanation:
K₂HPO₄ consist of anion and cation such as HPO₄²⁻ and K⁺. We can see that the charge on HPO₄²⁻ is negative 2. Thus inroder to balance the charge and to neutral the compound two potassium ions are attached because the charge on one atom of potassium is K⁺.
Properties of K₂HPO₄ :
It is salt of phosphoric acid.
Its density is 2.44 g/cm³.
It is odourless compound.
It is white powder and soluble in water.
It is used in fertilizer because it provide phosphorus which is beneficial for the growth of plants.
It is also used as a additive in food.
It is inorganic compound and also used as buffering agent.
Final answer:
The correct ions present in K2HPO4 are K+, H+, and PO43-. Here, potassium (K+) ions, hydrogen (H+) ion and phosphate (PO43-) ion are released.
Explanation:
The compound K2HPO4 dissociates in water to form ions. The correct answer from your selection would be the first one. When K2HPO4 is added to water, it dissociates into its ions 'K+' (Potassium), 'H+' (Hydrogen) and 'PO43-' (Phosphate). So, the ions present in K2HPO4 are K+, H+ and PO43-. Please note that K2HPO4 is also called dipotassium hydrogen phosphate.
Learn more about Ionic Dissociation here:
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