Which statement best explains why a carbon atom can bond easily with other atoms? It is an ion. It is an organic element. It has four valence electrons. It forms hydrogen bonds.
Hope this answers the question.
Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S(g) + 3F2(g) ->SF6(g) If 50 g S is allowed to react as completely as possible with 105.0g F2(g), what mass of the excess reactant is left.
S(g) + 3F2(g) ->SF6(g)
We are given the amount of the reactants to be used in the reaction. We use these as the starting values for the calculations. We calculate as follows:
50 g S ( 1 mol / 32.066 g ) = 1.56 mol S
105 g F2 ( 1 mol / 38.00 g ) = 2.76 mol F2
The limiting reactant would be F2 since it will be consumed completely in the reaction. The excess reactant would be S.
Mass of excess = 1.56 mol - 2.76(1/3) = 0.64 mol S excess
2C6H6 + 15O2 = 12CO2 + 6H2O
We are given the amount of benzene to be used in the reaction. We use this as the starting point for the calculations. We do as follows:
10.47 g C6H6 ( 1 mol / 78.1074 ) ( 15 mol O2 / 2 mol C6H6 ) ( 32 g / mol ) = 32.17 g O2
Which of the following statements is true about catalysts? and Why? a. Catalysts slow down the rate of chemical reactions b. All catalysts are enzymes c. Catalysts are used up during a chemical reaction d. Catalysts lower the activation energy of a chemical reaction
Your answer will be C. It's not D i just took the test
You carefully weigh out 14.00 g of CaCO3 powder and add it to 56.70 g of HCl solution. You notice bubbles as a reaction takes place. You then weigh the resulting solution and find that it has a mass of 64.96 g . The relevant equation is CaCO3(s)+2HCl(aq)→H2O(l)+CO2(g)+CaCl2(aq) Assuming no other reactions take place, what mass of CO2 was produced in this reaction?
Answer : The mass of produced will be, 6.16 grams.
Explanation : Given,
Mass of = 14 g
Mass of = 56.70 g
Molar mass of = 100 g/mole
Molar mass of = 36.5 g/mole
Molar mass of = 44 g/mole
First we have to calculate the moles of and .
Now we have to calculate the limiting and excess reagent.
The balanced chemical reaction is,
From the balanced reaction we conclude that
As, 1 moles of react with 2 mole of
So, 0.14 moles of react with moles of
From this we conclude that, is an excess reagent because the given moles are greater than the required moles and is a limiting reagent and it limits the formation of product.
Now we have to calculate the moles of .
As, 1 moles of react to give 1 moles of
So, 0.14 moles of react to give 0.14 moles of
Now we have to calculate the mass of .
Therefore, the mass of produced will be, 6.16 grams.
Answer: B.) > 0 = spontaneous reaction
The standard emf of a cell is related to Gibbs free energy by following relation:
= gibbs free energy
n= no of electrons gained or lost
F= faraday's constant
= standard emf
when = +ve, reaction is non spontaneous
= -ve, reaction is spontaneous
= 0, reaction is in equilibrium
Thus reaction is spontaneous when = +ve
Thus reaction is non spontaneous when = -ve
Thus reaction is in equilibrium when = 0.
Monel metal is a corrosion-resistant copper-nickel alloy used in the electronics industry. A particular alloy with a density of 8.80 g/cm3 and containing 0.073% Si by mass is used to make a rectangular plate that is 15.0 cm long, 12.5 cm wide, and 2.50mm thick and has a 2.50-cm-diameter hole drilled through its center such that the height of the hole is 2.50mm . The silicon in the plate is a mixture of naturally occurring isotopes. One of the those isotopes is silicon-30, which has an atomic mass of 29.97376 amu and a percent natural abundance of 3.10% How many silicon-30 atoms are found in this plate? Express your answer numerically using two significant figures.
Answer is: there are 1.82·10²⁰ silicon-30 atoms.
V₁(alloy) = 15 cm · 12.5 cm · 0.25 cm.
V₁(alloy) = 46.875 cm³; volume of the alloy without hole.
V(hole) = 0.25 cm · (1.25 cm)² · 3.14.
V(hole) = 1.23 cm³
V₂(alloy) = 46.875 cm³ - 1.23 cm³.
V₂(alloy) = 45.65 cm³; volume of the alloy with hole.
m(alloy) = V₂(alloy) · d(alloy).
m(alloy) = 45.65 cm³ · 8.80 g/cm³.
m(alloy) = 401.7 g; mass of the alloy.
ω(Si) = 0.073% ÷ 100%.
ω(Si) = 0.00073.
m(Si) = ω(Si) · m(alloy).
m(Si) = 0.00073 · 401.7 g.
m(Si) = 0.293 g; mass of silicon it the alloy.
m(Si-30) = m(Si) · ω(Si-30).
m(Si-30) = 0.293 g · 0.031.
m(Si-30) = 0.0091 g; mass of the silicon-30.
n(Si-30) = m(Si-30) ÷ M(Si-30).
n(Si-30) = 0.0091 g ÷ 29.97376 g/mol.
n(Si-30) = 0.000303 mol; amount of the silicon-30.
N(Si-30) = n(Si-30) · Na (Avogadro constant).
N(Si-30) = 0.000303 mol · 6.022·10²³ 1/mol.
N(Si-30) = 1.824·10²⁰.
Which of the following statements about ionization energy is true? A. In a period, elements farther to the right generally have lower ionization energies than elements on the left. B. Elements toward the bottom of a group periodic table generally have higher ionization energies than elements at the top of the group. C. Ionization energy is the amount of energy used to add an electron to an atom. D. Potassium has a lower ionization energy than sodium.
Lewis structures are shown below
- In Lewis structure of nitromethane, a negative charge is present on oxygen atom in nitro group.
- Hence this oxygen atom acts as a basic center preferably.
- Therefore conjugate acid of nitromethane should be drawn by adding a hydrogen atom with this oxygen atom.
- Lewis structure of nitromethane as well as it's conjugate acid has been shown below including all the lone pairs and formal charges
An unknown compound contains only carbon, hydrogen, and oxygen (CxHyOz). Combustion of 2.50g of this compound produced 3.67g of carbon dioxide and 1.50g of water. How many moles of carbon, C, were in the original sample?
C + O2 = CO2
Molar mass CO2 = 44 g/mol
3.67 g CO2 * 1 mol / 44 g =
=0.0834 mol CO2 = 0.0834 mol C
I hope my answer has come to your help. God bless and have a nice day ahead!
2. Distilled water does not have H+ & OH- ions, hence only H-bonds exist between the water molecules.
3. There are covalent bonds between the individual sugar molecules.
4. There are ionic bonds between the Na+ & Cl- ions in NaCl.
5. There are p.d.-p.d. forces of attraction between the Na+ ions and the O2- partial ions of the water molecules as well as between the Cl- ions and the H+ partial ions of the water molecules. There are also H-bonds between the individual water molecules and ionic bonds between the Na+ & Cl- ions (although these are in much lower abundance than in unsolvated solid NaCl).
6. There are i.d.-i.d. as well as p.d.-p.d. forces of attraction between the sugar molecules and the water molecules. There are also H-bonds between the individual water molecules and covalent bonds within the sugar molecules.
A teacher makes the following statement. “Gasoline boils at a relatively low temperature (about 150°C). The kerosene is removed at around 200°C, followed by diesel oil at 300°C and fuel oil at around 370°C.” What topic is the teacher most likely talking about? a. distillation of a mixture b. filtration of a pure substance c.evaporation of a mixture d. sorting of a pure substance
The correct answer is option a.
According the question, boiling points of different liquids are discussed which means that if we take all these liquids in single mixture we can separate them from each other on the basis of their difference in boiling point. And the technique which employs this principle is distillation process.
Hence, we can say teacher is most likely talking about distillation of a mixture of oils.
Distillation is a process which is used to separate mixture of different liquids from each other. In this process, during the course of boiling of mixture liquid compound with lower boiling points vaporizes first leaving behind the liquid with higher boiling point behind.
And vapors of boiled liquid are condensed down in a separate container for the collection.
An element belongs to particular group is related to the number of electrons present in the outer shell of the atoms. In given case, group is 2, therefore, number of valence electrons is 2 implies it has ability to lose two electrons to get +2 charge.
Therefore, ion formed after removal of two electrons is .
Hence, option (D) is the correct answer.
Which contributes to the dissolution of sugar in water? a. the dissociation of an ionic compound in water b. a strong pull of water molecules on an ionic compound c. the dissociation of a polar covalent compound in water d. a strong pull of water molecules on a polar covalent compound
Option C: The dissociation of a polar covalent compound in water.
Sugar is made up of sucrose molecules containing polar covalent bonds. They have same type of oxygen-hydrogen covalent bonds that are present in water.
Since, sugar is not an ionic compound, option a and option b are incorrect. Also, due to same type of bonding in water and sugar molecules there will be no such force of attraction between them, this will opt out the option d.
Thus, dissolution of sugar in water is the dissociation of a polar covalent compound in water and option c is correct.
Answer: 1.6 gram
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number of particles.
To calculate the moles, we use the equation:
1 mole of Platinum weighs 195 g
of Platinum weigh =
Thus mass of platinum atoms is 1.6 gram.
Which of the following statements about the use of nuclear energy is true? a. Nuclear energy cannot be used safely. b. Nuclear fusion has no known useful applications. c. Nuclear fission is currently more useful for producing energy than nuclear fusion. d. Nuclear fusion has fewer safety risks than nuclear fission.
Nuclear energy cannot be used safely.
I hope my answer helped you
Which of these is a property of a substance that is composed of atoms that are held together by ionic bonds? It can be shaped into wires. It has a low melting point. It conducts electricity when in solid form. It conducts electricity when it is dissolved in water.
Answer: Option (D) is the correct answer.
A ionic compound will have opposite charges on the 2 atoms attached to each other.
When ionic compound is in solid state then atoms will be more closer to each other and also due to the opposite charges the molecules will have strong force of attraction between them.
In order to conduct electricity, free movement of ions is required. So, a solid with ionic bonds is not able to conduct electricity as molecules or ions are closely held together.
Whereas when a substance that is composed of atoms that are held together by ionic bonds is dissolved in water then its ions will start to move freely from one point to another. Thus, this solution will be able to conduct electricity.
Thus, we can conclude that out of the given options, conducts electricity when it is dissolved in water displays a property of a substance that is composed of atoms that are held together by ionic bonds.
Answer: Option (a) is the correct answer.
When a fat contains high proportion of fatty acid molecules which have no double bonds then it is known as a saturated fat.
For example, animal fats are mostly saturated.
Fats which are solid at room temperature are known as solid fats. Butter, beef fat etc are all solid at room temperature. Most of the animal food gives solid fats.
Thus, we can conclude that saturated fat is most likely a solid at room temperature.
The Kingdom of Tonga is a Polynesian Archipelago in Oceania consisting of 176 islands. During a month long coral reef research mission in Tonga, the Foundation focused on islands in the Ha’aipi group, Vava’u and Niuatoputapu. Haʻapai, directly west of the Tonga trench in the central part of Tonga, is made up of 51 volcanic islands and includes Kao, the highest point in the kingdom (1,046 m). Vavaʻu has one large island and 40 smaller ones, and includes the second largest city, a large harbor. The north side of the main island is lined by 200 m high cliffs and extensive open network of fjord-like channels that stretch inland on the north side. Nearly 300 km north of Vavaʻu, close to the border of Samoa is Niuatoputapu, a sparsely inhabited (population 150) eroded remnant of a volcano surrounded by a large uplifted reef. This island was badly damaged by a tsunami following a submarine earthquake off Samoa in 2009.
This is the fourth macro-molecule being described.
If this answer helped you, please vote me as brainliest!
Answer: The order with respect to B is
Explanation: Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
k= rate constant
x = order with respect to A
y = order with respect to B
n = x+y = Total order
a) From trial 1: (1)
From trial 2: (2)
Dividing 2 by 1 :
Thus order with respect to B is 1.