Alkali metals tend to be more reactive than alkaline earth metals because ________. Alkali metals tend to be more reactive than alkaline earth metals because ________. alkali metals have lower melting points alkali metals have lower densities alkali metals have greater electron affinities alkali metals have lower ionization energies Alkali metals are not more reactive than alkaline earth metals.

Answer:

Half life =  1.540 s

Explanation:

A → 3B+2C

Initial concentration = 0.535 mol L−1

rate constant k = 0.450 s-1

half life t1/2 = ?

Since the reaction s a first order reaction

Half life is given by;

t1/2 = 0.693 / k

t1/2 = 0.693 / 0.450 = 1.540 s

Answer:

The most basic solution is A

Explanation:

In order to solve the problem, we can compare the pH of the solutions. The most basic solution is the one with the highest pH.

A. [H⁺] = 1 × 10⁻¹⁰ M

pH = - log [H⁺] = - log (1 × 10⁻¹⁰) = 10

B. pOH = 6.7

pH = 14 - pOH = 14 - 6.7 = 7.3

C. [OH⁻] = 7 × 10⁻⁵ M

pOH = - log [OH⁻] = -log (7 × 10⁻⁵) = 4.15

pH = 14 - pOH = 14 - 4.15 = 9.8

D. pH = 4.2

According to this, solution A has the highest pH (pH=10), thus this is the most basic solution.

Answer:

homolytic cleavage of a covalent bond.

Explanation:

Homolytic cleavage: In chemistry, the term "homolytic cleavage" is described as a process that involves breaking of a particular covalent bond in a way that every fragment tends to get "one" shared electrons and it often produces or gives rise to free radicals. It is also referred to as "homolysis" or "homolytic bond cleavage".

In the question above, the given statement represents "homolytic cleavage of a covalent bond".

Answer:

H₂CO₃(aq) ⇄ H⁺(aq) + HCO₃⁻(aq)   K₁ = [H⁺][HCO₃⁻]/[H₂CO₃]

HCO₃⁻(aq) ⇄ H⁺(aq) + CO₃²⁻(aq)    K₂ = [H⁺][CO₃²⁻]/[HCO₃⁻]

Explanation:

Let's consider the equation for the first step of the ionization of carbonic acid.

H₂CO₃(aq) ⇄ H⁺(aq) + HCO₃⁻(aq)

The first ionization constant is:

K₁ = [H⁺][HCO₃⁻]/[H₂CO₃]

Let's consider the equation for the second step of the ionization of carbonic acid.

HCO₃⁻(aq) ⇄ H⁺(aq) + CO₃²⁻(aq)

The second ionization constant is:

K₂ = [H⁺][CO₃²⁻]/[HCO₃⁻]

Explaining the concept:

Molar mass of an element is the mass of 6.022*10²³ atoms of that element

a group of 6.022*10²³ atoms or molecules is called 1 mole of that specific element or compound

this number is so large that even though atoms are very small, 6.022*10²³ of them weigh several grams depending on the element the atom belongs to.

Atoms with a larger atomic number have more protons and neutrons than atoms with small atomic number; more protons and neutrons means that they have more matter and hence, more mass

that's why elements with a large atomic number are heavier

for example:

the molar mass (mass of 1 mole or 6.022*10²³ atoms) of hydrogen is approximately '1' grams per mole

whereas,

the molar mass of Carbon (C), (which has only 5 electrons more than hydrogen) is 12 grams per mole

Solving the question:

Finding the number of Moles:

We are given 5.4 grams of Boron (B)

the molar mass of boron is 11 grams per mole

To calculate the number of moles of an element, we divide the given mass by the molar mass

Number of moles = Given mass / Molar mass

Number of moles = 5.4 / 11

Number of moles = 0.5 (approx)

Finding the number of Atoms:

Now that we have the number of moles, we can easily find the number of atoms by dividing it by 6.022*10²³ (since a group of 6.022*10²³ atoms is 1 mole)

Number of Atoms = Number of moles * 6.022*10²³

Number of atoms = 0.5 * 6.022*10²³

Number of atoms = 3.011 * 10²³

Answer:

7.133 g/cm^3

Explanation:

Density = mass ÷ volume

Given,

mass = 14.98 g

Volume = 2.10 ml = 2.10cm^3 [because 1 ml= 1cm^3]

density = 14.98÷ 2.10

density = 7.133 g/cm^3

Answer:

[tex]\boxed {\tt d\approx7.13 \ g/mL}[/tex]

Explanation:

The density of an object can be found by dividing the mass by the volume.

[tex]d=\frac{m}{v}[/tex]

The mass of the cylinder is 14.98 grams.

The volume of the cylinder is 2.10 milliliters.

[tex]m=14.98 \ g\\v= 2.10 \ mL[/tex]

Substitute the values into the formula.

[tex]d=\frac{14.98 \ g}{2.10 \ mL}[/tex]

Divide.

[tex]d=7.13333333 \ g/mL[/tex]

Round to the nearest hundredth. The 3 in the thousandth place tells us to leave the 3 in the hundredth place.

[tex]d\approx 7.13 \ g/mL[/tex]

The density of the cylinder is about 7.13 grams per milliliter.

Answer:

question no 4 answer is electrons

Answer:

brittle crust and top is made of upper mantel

Answer:

Group 8A (or VIIIA) of the periodic table are the noble gases or inert gases: helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). The name comes from the fact that these elements are virtually unreactive towards other elements or compounds.

Explanation:

its XE

Answer:

Negative

Explanation:

Because i learned it in 5th grade

Answer:

negative

Explanation:

When you are missing an electron or two, you have a positive charge. When you have an extra electron or two, you have a negative charge.

Answer: Shiny

Explanation:

Answer:

Every substance has its own melting point and boiling point . The stronger the forces between particles, the higher its melting and boiling points. For example, the forces between ions in an ionic solid are stronger than those between molecules in water or hydrogen.

Explanation:

Answer:

They are extremely hotter and the molten lava is being boiled by the earth.

Explanation:

By: Dreamy Illumination

Answer:

231.59 mL

Explanation:

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

Initial volume (V₁) = 125 mL

Initial temperature (T₁) = 300 k

Initial pressure (P₁) = 2.39 atm

Final temperature (T₂) = 500 k

Final pressure (P₂) = 2.15 atm

Final volume (V₂) =..?

The new volume of the gas (V₂) can be obtained by using the combined gas equation as shown below:

P₁V₁ /T₁ = P₂V₂ /T₂

2.39 × 125 /300 = 2.15 × V₂ /500

Cross multiply

300 × 2.15 × V₂ = 2.39 × 125 × 500

645 × V₂ = 149375

Divide both side by 645

V₂ = 149375/645

V₂ = 231.59 mL

Therefore, the new volume of the gas is 231.59 mL

Answer: Oxygen or carbon I’ll say oxygen

Explanation:

Answer:

Adrenal and Hypothalamus!

Explanation:

Hope this helps!

Answer:

A man is walking in the park at night when he sees a shadow suddenly dart across his path. Which glands will be responsible for controlling his “fight or flight” reaction? Check all that apply.

Adrenal and Hypothalamus

A woman goes to the doctor for blood tests because she has not been feeling well. Tests show that the sugar levels in her blood are too high. In which gland does she most likely have a problem?

Pancreas

Explanation:

Answer:

5.6 x 10¹⁴m

Explanation:

Given parameters:

Wavelength  = 5.4 x 10⁻⁷m

Unknown:

Frequency of the electromagnetic radiation = ?

Solution:

The speed of all electromagnetic radiation is given as 3.0 x 10⁸m/s

  So;

         Speed = frequency x wavelength

  Wavelength = [tex]\frac{speed}{frequency}[/tex]

 Insert the parameters and solve;

   Wavelength = [tex]\frac{3 x 10^{8} }{5.4 x 10^{-7} }[/tex]  

  Wavelength  = [tex]\frac{3}{5.4}[/tex]  x 10⁸⁻⁽⁻⁷⁾

  Wavelength  = 5.6 x 10⁻¹ x 10¹⁵

   Wavelength  = 5.6 x 10¹⁴m

Answer:

Limiting Reactant is going to be NaOH or HCl with given lowest moles. Excess will be the ones with more.

Explanation:

Excess and Limiting reactants are based on the amount you could make in an ideal reaction. M (molarity) is the concentration of the given solutions where moles in the amount (the important part) you have of each. If you only have 0.0100 mol NaOH while you have 0.0400 mol HCl the most a reaction has the potential to use is that 0.0100 mol NaOH, thus making it the limiting reactant as it is limiting the possible amount made. The excess here is 0.0300 mol HCl.

Answer:

O Winds spiraling dowrward and away from the center of a storm.

Explanation:

this is correct

Answer:

62.174

Explanation:

volume = mass/density

143/2.3 = 62.174

Explanation:

A polyatomic ion refers to an ion that contains more than one atom.

Potassium Bicarbonate contains the Potassium ion and bicarbonate ion.

The formula is given as; KHCO₃

Aluminium Phosphate contains the Aluminium ion and Phosphate ion.

The formula is given as; AlPO4

Copper(II)hydroxide contains copper ion and hydroxide ion.

The formula is given as; Cu(OH)₂

Answer:

so if an atom needs and electron it will form a bond with another so it will balance out.

Explanation:

Answer:

A. Mo

Explanation:

The given electron configuration: 1s22s22p63s23p64s23d104p65s24d4 shows 42 electrons and Molybdenum has atomic number 42.

But the correct electronic configuration of molybdenum is  [Kr]4d5 5s1, and not [Kr]5s24d4 which is based on the diagonal rule.

The diagonal rule states that a half full 5s subshell and half-full 4d subshell are more stable than a full 5s subshell and 4d filled with four electrons.

Hence, the correct element is "A. Mo".

Answer:

[tex]-8.032\ \text{kJ/mol}[/tex]

Explanation:

m = Mass of mixture = 62.6 g

n = Number of mole of reactant = 0.15 mol

[tex]\Delta T[/tex] = Change in temperature = [tex]4.6^{\circ}\text{C}[/tex]

c = Specific heat of mixture = [tex]4.184\ \text{J/g}^{\circ}\text{C}[/tex] (assumed to be the same as water)

Heat generated

[tex]Q=mc\Delta T\\\Rightarrow Q=62.6\times 4.184\times 4.6\\\Rightarrow Q=1204.82\ \text{J}=1.20482\ \text{kJ}[/tex]

Heat of reaction is given by

[tex]\Delta H=-\dfrac{Q}{n}\\\Rightarrow \Delta H=-\dfrac{1.20482}{0.15}\\\Rightarrow \Delta H=-8.032\ \text{kJ/mol}[/tex]

The heat of the reaction is [tex]-8.032\ \text{kJ/mol}[/tex]

A 62.6 g-reaction mixture that contains 0.15 moles of reactant A and causes a temperature increase of 4.6 °C in a calorimeter, has a heat of reaction of -8.0 kJ/mol.

We have a reaction mixture in a calorimeter that causes a temperature increase of 4.6 °C (ΔT). We can calculate the heat absorbed by the solution (Qs) using the following expression.

[tex]Qs = c \times m \times \Delta T = \frac{4.184J}{g.\° C} \times 62.6 g \times 4.6 \° C \times \frac{1kJ}{1000J} = 1.2 kJ[/tex]

where,

According to the law of conservation of energy, the sum of the heat absorbed by the solution and the heat released by the reaction (Qr) is zero.

[tex]Qs + Qr = 0\\\\Qr = -Qs = -1.2 kJ[/tex]

1.2 kJ are released by the reaction of 0.15 moles of reactant A. The heat of the reaction, in kJ/mol, is:

[tex]\frac{-1.2kJ}{0.15mol} = -8.0 kJ/mol[/tex]

A 62.6 g-reaction mixture that contains 0.15 moles of reactant A and causes a temperature increase of 4.6 °C in a calorimeter, has a heat of reaction of -8.0 kJ/mol.

Learn more: https://brainly.com/question/20250226

Answer:

C

Explanation:

1. Cascade Range, segment of the Pacific mountain system of western North America. The Cascades extend northward for more than 700 miles (1,100 km) from Lassen Peak, in northern California, U.S., through Oregon and Washington to the Fraser River in southern British Columbia, Canada.

2.The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades.

3.The Cascade Volcanoes were formed by the subduction of the Juan de Fuca, Explorer and the Gorda Plate (remnants of the much larger Farallon Plate) under the North American Plate along the Cascadia subduction zone.

4.What are Plate Boundaries? Plate boundaries are the edges where two plates meet. Most geologic activities, including volcanoes, earthquakes, and mountain building, take place at plate boundaries.

5.Contents

1 Divergent boundaries.

2 Convergent boundaries (subduction zone)

3 Orogenic belts.

4 Transform boundaries.

____________________

6.Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced to sink due to high gravitational potential energy into the mantle. ... Subduction zones are sites that usually have a high rate of volcanism and earthquakes.

7.The Ring of Fire is a major area in the basin of the Pacific Ocean where many earthquakes and volcanic eruptions occur.

8.The impact of the colliding plates can cause the edges of one or both plates to buckle up into a mountain ranges or one of the plates may bend down into a deep seafloor trench. A chain of volcanoes often forms parallel to convergent plate boundaries and powerful earthquakes are common along these boundaries.

Answer:

597K

Explanation:

Given parameters:

Initial pressure = 1.2atm

Initial temperature = 125°C = 125 + 273 = 398K

Initial volume = 1.00L

Final pressure = 1.80atm

Final volume  = 1.00L

Unknown:

Final temperature = ?

Solution:

To solve this problem, we must understand that at constant volume, the pressure of a given mass of gas varies directly with the absolute temperature.

Mathematically;

              [tex]\frac{P_{1} }{T_{1} }[/tex] = [tex]\frac{P_{2} }{T_{2} }[/tex]

where P and T are the pressures

           1 and 2 are the initial and final states

Now insert the parameters and solve;

         [tex]\frac{1.2}{398}[/tex]   = [tex]\frac{1.8}{T_{2} }[/tex]

         T₂ x 1.2 = 398 x 1.8

         T₂ = 597K

Answer:

the answer is in the screenshot

Explanation:

hope this helps

Moles of any substance is given by the molar mass and the mass. The volume of EDTA required to titrate is 3.16 mL and the volume of zinc required to titrate is 22.8 mL.

Molarity is the property of the solution that gives the concentration of the solute present in the solution.

Given,

Mass of cobalt sulfate = 1.697 gm

The molar mass of cobalt sulfate = 155 g/mol

In the first part, the volume of the aliquot is 25 mL and the molarity is 0.08640 M.

The reaction is shown as:

Co²⁺ + H₄Y → CoH₂Y + 2H⁺

Moles of cobalt: n = 0.001694 ÷ 155 = 0.0000109 moles

In 25 ml aliquot moles of cobalt are, 0.000273 moles.

The volume of EDTA solution is calculated as:

V = moles ÷ Molarity

= 0.000273 mole ÷ 0.0864 mol/ L

= 3.16 mL

Hence, 3.16 mL of EDTA is required.

For the second part, moles of EDTA are calculated as:

n = 0.008640 × 0.050 = 4.32 ×10⁻⁴

In a 25 mL, sample moles of EDTA are 2.16 × 10⁻⁴ moles.

Excess moles of EDTA in the solution:

0.000432 - 0.000216 = 0.000216 moles

The volume of EDTA is calculated as:

V = 0.000216 ÷ 0.009450

= 0.0228 L

Hence, 22.8 mL of zinc is required.

Learn more about molarity here:

https://brainly.com/question/22714469

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