24. H2SO4 has
a) ionic bond
b) both Ionic and covalent bonds
c) ionic, covalent and coordinate bonds
d) covalent bond​

Answer:

Mass percentage of TiO2 in the ore = 5.04%

Mass percentage of Ti = 3.01%

Explanation:

Equation of reaction is given below:

3 TiO2(s) + 4 BrF3(l) ---> 3 TiF4(s) + 2 Br2(l) + 3 O2(g)

From the equation of reaction above, 3 moles of O2(g) is obtained from 3 moles of TiO2(s)

Molar mass of O2 = 32 g/mol; molar mass of TiO2 = 79.87 g/mol, molar mass of Ti = 47.87 g/mol

Number of moles of O2 in 32.1 mg or 0.0321 g of O2 = 0.0321 g/32 g/mol = 0.001 moles

Therefore, 0.001 moles of O2 will be obtained from 0.001 moles of TiO2

Hence, mass l of 0.001 moles of TiO2 = 0.001 moles x 79.87g/mol = 0.07987

Mass percentage of TiO2 in the ore = 0.07987 x 100/1.586 = 5.04%

Mass of Ti in sample = (0.07987 - 0.03210) g = 0.04777 g

Mass percentage of Ti = 0.04777 × 100/1.586 = 3.01%

Answer:

percentage of red skittles = 22%

percentage of skittles that are not green = 74%

Explanation:

total skittles = 50

yellow = 12

orange = 9

red = 11

green = 13

purple = 50-12-9-11-13

= 5

1) percentage of red skittles

[tex] \frac{red \: skittles}{total \: skittles} \times 100[/tex]

[tex] \frac{11}{50} \times 100[/tex]

[tex] \frac{22}{10} [/tex]

[tex]22\%[/tex]

2) percentage of skittles that are not green

[tex] \frac{total \: skittles - green \: skittles}{total \: skittles} \times 100[/tex]

[tex] \frac{50 -13 }{50} \times 100[/tex]

[tex] \frac{37}{50} \times 100[/tex]

[tex]74\%[/tex]

Answer:

c. the major gases that make up only the troposphere

Explanation:

Oxygen (O2) and nitrogen (N2) are the major gases that make up only the troposphere because both oxygen and nitrogen are heavy gases which is present at lower height so it comes under the troposphere layer while on the other hand, ozone gas that act as a filter for harmful radiation of the sun is present in the stratosphere which is present next to troposphere layer of atmosphere.

Answer:

I can answer 1, lqva is magma outside of the volcano

Answer:

A homogeneous mixture is a mixture in which the components that make up the mixture are uniformly distributed throughout the mixture.

Explanation:

Answer:

c. enzyme activity is usually least active below its optimum pH

Explanation:

Enzyme activity depends highly on pH. Enzymes are biological molecules which are proteins and influence the rates of important biochemical reactions in the human body.

Enzymes has a value of pH at which it works most perfectly. This pH value is known as its optimum pH. Above or below this value, the enzyme does not function optimally.

Hence, a change in pH usually produces a change in enzyme activity because enzyme activity is usually least active below its optimum pH

This question is incomplete, the complete question is;

The equilibrium constant, Kc, for the following reaction is 7.00×10-5 at 673 K. NH4I(s) ---> NH3(g) + HI(g) Calculate the equilibrium concentration of HI when 0.343 moles of NH4I(s) are introduced into a 1.00 L vessel at 673 K

Answer:

the equilibrium concentration of HI is 1.302 × 10⁻⁵ M

Explanation:

Given that;

kc = 7.00 × 10⁻⁵ at 673 K

equilibrium concentration of HI = ?

when 0.343 moles of NH4I(s) are introduced into a 1.00 L vessel at 673 K

Molarity of NH4I = 0.343 / 1.00 = 0.343 M

NH4I(s) -----------------> NH3(g) + HI(g)

0.343                             0           0   ------> Initial

(0.343 - x)                        x            x   -------> equilibrium

we know that; solid does not take part in equilibrium constant expression

so

KC = [NH3] [HI] / NH4I

we substitute

7.00 × 10⁻⁵ = x² / (0.343 - x)  

0.00007 (0.343 - x) = x²

0.00002401 - 0.00007x = x²

x² + 0.00007x - 0.00002401 = 0

using; x = -b±√(b² - 4ac) / 2a

we substitute

x = -0.00007 ± √((0.00007)² - 4×1×-0.00002401) / 2×1

x = [-0.00007 ± √( 4.9×10⁻⁹ + 9.604×10⁻⁵)] / 2

x = [-0.00007 ± 0.00009604] / 2

Acceptable value of x = [-0.00007 + 0.00009604] / 2

x = 0.00002604 /2

x = 0.00001302 ≈ 1.302 × 10⁻⁵ M

therefore the equilibrium concentration of HI is 1.302 × 10⁻⁵ M

Answer:

The bubble goes into the atmosphere.

Explanation:

All the dissolved air evaporated from the water when there is 1 atmospheric pressure for a long time because the air is dissolved with high pressure so when the pressure is removed from the gas present in water. The bubble go away from the water solution due to more kinetic energy present in it as compared to lower atmospheric pressure.

Answer:

Answers are given below

Explanation:

Significant figures:

When we add or subtract the values the number of significant figures after decimal in result must be equal to the given measurement having less number of decimal places.

b) 5.45 -2.3

3.2

d) 14.98 + 27,340 + 84.7593

27439.74

When we multiply or divide the values the number of significant figures must be equal to the less number of significant figures in given value.

a) 628 × 342

214776

we will round off this value into 3 significant figures.

215000

c) 28.0/13.483

2.08

Explanation:

[tex]IO_2^-[/tex] is the Iodite ion. The ion has a total of 7+6(2)+1 = 20 electrons. The Iodite ion, or iodine dioxide anion, is the halite with the chemical formula IO−

2. Within the ion the Iodine exists in the oxidation state of +3. The hybridization state of central atom I in Iodite ion is [tex]d^2sp^3[/tex].

Answer:

B. Nitrogen

Explanation:

Hope this helps :)

The answer is nitrogen gas.

Answer:

d

Combustion

Explanation:

Answer:

Option B. 3.0 M

Explanation:

From the question given above, the following data were obtained:

Volume of solution = 3.0 L

Mole of MgCl₂ = 9 moles

Molarity =?

Molarity can simply be defined as the mole of solute per unit litre of the solution. Mathematically, it can be expressed as:

Molarity = mole of solute /Volume of solution

With the above formula, we can obtain the molarity of the solution as follow:

Volume of solution = 3.0 L

Mole of MgCl₂ = 9 moles

Molarity =?

Molarity = mole of solute /Volume of solution

Molarity = 9 / 3

Molarity = 3 mol/L = 3.0 M

Thus, the molarity of the solution is 3 M

Answer:

C. Cutting your hair

Explanation:

A physical change is one of the two types of changes in nature (the other being chemical change). A physical change does not affect the chemical composition of the substance(s) involved.

In this case, "CUTTING ONE'S HAIR" is an example of physical change because it involves the removal of the hair without altering the chemical composition of the hair. However, other examples given in the options of this question like digestion of food, getting a suntan (change in skin coloration), and growth in height all involve a change in the chemical nature of the parts involved, hence, they are examples of chemical changes.

Answer:

F-

Explanation:

The atomic radius of F is 72 pm and that of F- is 136 pm.

Answer:

distillation

Explanation:

distillation is better suited separation method

Answer:

Option E. Zirconium

Explanation:

From the question given above, the following data were obtained:

Length of side (L) of cube = 0.2 cm

Mass (m) of cube = 52 mg

Name of the unknown metal =?

Next, we shall determine the volume of the cube. This can be obtained as follow:

Length of side (L) of cube = 0.2 cm

Volume (V) of the cube =?

V = L³

V = 0.2³

V = 0.008 cm³

Next, we shall convert 52 mg to g. This can be obtained as follow:

1000 mg = 1 g

Therefore,

52 mg = 52 mg × 1 g / 1000 mg

52 mg = 0.052 g

Thus, 52 mg is equivalent to 0.052 g.

Next, we shall determine the density of the unknown metal. This can be obtained as follow:

Mass = 0.052 g.

Volume = 0.008 cm³

Density =?

Density = mass / volume

Density = 0.052 / 0.008

Density of the unknown metal = 6.5 g/cm³

Comparing the density of the unknown metal i.e 6.5 g/cm³ with those given in table in the above, we can conclude that the unknown metal is zirconium

the percent of hydrogen by mass in HNO3 is 1.600%

Answer:

[tex]\boxed {\boxed {\sf 1.5996953 \%\ or \ 1.6 \%}}[/tex]

Explanation:

Percent composition tells us the mass percentage of an element in a compound. It can be found by dividing the mass of the element by the mass of the compound, then multiplying by 100.

[tex]\frac{element \ mass}{compound \ mass} *100[/tex]

1. Compound Mass

The compound given is HNO₃

Use the Periodic Table to find the masses of each element.

Next, multiply each element's mass by the number of atoms, then add them together.

2. Percent Composition

Now we know that HNO₃'s mass is 63.012 u. This is the compound mass.

We want to find the percent of hydrogen and its mass is 1.008 u. This is the element mass.

[tex]\frac{1.008 \ u }{63.012\ u } *100[/tex]

[tex]0.015996953*100[/tex]

[tex]1.5996953[/tex]

This can be rounded to the nearest tenth. The 9 in the hundredth place tells us to round the 5 to a 6.

[tex]\approx 1.6[/tex]

The percent of hydrogen in HNO₃ is 1.5996953% or about 1.6%

Answer:

Concentration cell

Explanation:

Galvanic cells and even electrolytic cells usually consist of two electrodes namely anode and cathode. These 2 electrodes can either be made of the same metals or different metals, and also an electrolyte whereby the two electrodes are immersed.

Now, in the case where the electrodes are made of the same metal, we call it a concentration cell because A concentration cell is a cell that consists of two half-cells that have the same electrodes, but yet differ in concentrations.

Pure metals possess few important physical and metallic properties, such as melting point, boiling point, density, specific gravity, high malleability, ductility, and heat and electrical conductivity. These properties can be modified and enhanced by alloying it with some other metal or nonmetal, according to the need.

Alloys are made to:

Enhance the hardness of a metal: An alloy is harder than its components. Pure metals are generally soft. The hardness of a metal can be enhanced by alloying it with another metal or nonmetal.

Lower the melting point: Pure metals have a high melting point. The melting point lowers when pure metals are alloyed with other metals or nonmetals. This makes the metals easily fusible. This property is utilized to make useful alloys called solders.

Enhance tensile strength: Alloy formation increases the tensile strength of the parent metal.

Enhance corrosion resistance: Alloys are more resistant to corrosion than pure metals. Metals in pure form are chemically reactive and can be easily corroded by the surrounding atmospheric gases and moisture. Alloying a metal increases the inertness of the metal, which, in turn, increases corrosion resistance.

Modify color: The color of pure metal can be modified by alloying it with other metals or nonmetals containing suitable color pigments.

Provide better castability: One of the most essential requirements of getting good castings is the expansion of the metal on solidification. Pure molten metals undergo contraction on solidification. Metals need to be alloyed to obtain good castings because alloys

Answer:

No, ΔE does not always equal zero because it refers to the systems internal energy, which is affected by heat and work

Explanation:

According to the first law of thermodynamics, energy is neither created nor destroyed. This implies that the total energy of a system is always a constant.

So, according to the first law of thermodynamics we have that ΔE = q + w. This means that the value of  ΔE depends on q (heat) and  w(work). Hence ΔE is not always zero since it depends on the respective values of q and w.

Answer:

Gravity, Inertia, and Velocity ( I decided to use three)

Explanation:

Gravity is the primary force that controls orbit and gravity works with inertia along with velocity.

Gravity, Inertia, and Velocity ( I decided to use three)

Explanation:

Gravity is the primary force that controls orbit and gravity works with inertia along with velocity.

Answer:

c. Fe2+

Explanation:

Coordination compounds comprise solely complex ions together with one or more counter ions. They are compounds in which metal atoms or ions are directly bonded to anions or neutral atoms in conjunction with coordinate covalent bonds.

From the given options, only Fe2+ can form both low-spin and high-spin.

To determine that, we find out the number of unpaired spins in Fe2+

At the ground state:

The electronic configuration is:

Fe: [Ar] 3d⁶ 4s²

After the removal of two electrons, the configuration becomes

Fe²⁺ : [Ar] 3d⁶

A metal ion has the ability to form both low-spin and high-spin complexes if the metal-ion comprises more than 3 and less than 8 d -electrons.

So, since Fe²⁺  contains more than 3 and less than 8. Then Fe²⁺  is the right option.

Ti²⁺ contains only two d electrons

Cu⁺ contains more than eight d electrons

Ni²⁺ contains eight d electrons

Cr³⁺ contains three d electrons

Answer:

2.78 x 10²³

Explanation:

1 mole contains 6.02 x 10²³ hydrogen atoms => 0.46 mole contains 0.46(6.02 x 10²³) hydrogen atoms or 2.78 x 10²³ atoms.

Caution => When to use H vs H₂ => This problem is specific for 'hydrogen atoms' but some may simply say hydrogen. In such cases use H₂ or 'molecular hydrogen' is the focus. it's a matter of semantics, H vs H₂.    

Answer: b. False

Explanation:

The more energetic molecules move to a gas, spread out, and form bubbles when heating happens. When exposed to heat, many of the chemicals used in the laboratory are volatile and harmful (fire).

So leaving a material that you heat for even a second can be very hazardous and negligent.

Answer:

C. Water falls from the sky as rain. The water then flows downhill.

Explanation:

Water cycle can be defined as a process which typically involves the circulation (movement) of water between the Earth's atmosphere, land and ocean under various atmospheric conditions such as precipitation (rain and snow), transpiration, condensation and evaporation.

Basically, the movement of the water starts from the sky due to the condensation of water vapor to form clouds and later result to rainfall. Consequently, the rain water are either soaked by the soil or are made to flow down the hill.

The statement which best describes a way in which water moves in the water cycle is that, water falls from the sky as rain. The water then flows downhill or seeps into the ground.

Answer:

hey buddy,This's your answer...!!

Answer:

A

Explanation:

Answer:

think it is D

Explanation:

hope this helps

Answer:

Molarity = 0.27 M

Explanation:

Given data:

Volume of solution = 820 mL (820/1000 = 0.82L)

Mass of KI = 36.52 g

Molarity of solution = ?

Solution:

Number of moles of KI:

Number of moles = mass/molar mass

Number of moles = 36.52 g/ 166 g/mol

Number of moles = 0.22 mol

Molarity = number of moles / volume in L

Molarity = 0.22 mol / 0.82 L

Molarity = 0.27 M