9. Sodium reacts with water to produce sodium hydroxide and hydrogen gas, as shown below.

___________ is the scale used to describe how acidic or basic a solution is. This affects the enzymes within living systems.

nydimaria [60]

Answer:

pH scale

Explanation:

pH scale -

In the field of chemistry , the accurate and exact value of acidity or basicity in a particular solution is calculated with the help of a pH scale .

The scale has reading ranging from 1 to 14 ,

where ,

If the pH value less than 7 indicates the solution to be acidic in nature ,

If the pH value is exactly equal to 7 , the solution is neutral in nature ,

and ,

If the pH value more than 7 indicates the solution to be basic in nature ,

Hence , from the given statement of the question ,

The correct answer is pH scale .

3 0

3 years ago

Explain two advantages and disadvantages of using energy created by nuclear fission and nuclear fusion.

alisha [4.7K]

A. NUCLEAR FUSION is the combination of two atomic nuclei in order to create an atom that in turn creates energy.

A.1 DISADVANTAGES

1. Expensive Construction Costs- To be able to put up such powerhouse, it needs ostentatious financial support to create a facility and gather experts and scientists.

2. Energy Input vs Energy Output- To be able to fuse the two nuclei together, there is a great demand for high levels of heat. Thus to be able to produce large amount of energy, it also needs a large amount of thermal energy which is not reasonable enough.

A.2 ADVANTAGES

1. Barely Any Waste- the only by product of nuclear fusion is helium and it is non toxic. This does not cause any harm to the environment and to people.

2. Unlimited Fuel- All of the components needed to produce energy can be made. Deuterium, which is the main ingredient needed to supply a truly unlimited and sustainable energy supply, can be distilled from the sea water.

B. NUCLEAR FISSION- refers to the process of splitting of the nucleus of an atom into several smaller particles to produce free neutrons and lighter elements.

B.1 DISADVANTAGES

1. It can be dangerous for employees- Radiation which is one of the byproducts of nuclear fission can be harmful to the personnel working within its premises.

2. It has high initial expenses- Nuclear power plants needs a specialized equipment for it to become functional.

B.2 ADVANTAGES

1. It helps minimize environmental pollution- Nuclear power plants can produce large amounts of energy while consuming relatively minimal amount of fossil fuel. To explain further, consumption and usage of fossil fuel poses adverse effect in the environment because it can emit carbon dioxide and other harmful chemicals.

2. It helps reduce global warming- If the world would opt for nuclear fission, then there would be less greenhouse gasses in the atmosphere. This in turn would mitigate global warming.

3 0

4 years ago

If the methane contained in 2.50 L of a saturated solution at 25 ∘C was extracted and placed under STP conditions, what volume w

Sunny_sXe [5.5K]

116.6 x $10^{ -3$ } is the volume of methane contained in 2.50 L of a saturated solution at 25 ∘C that was extracted and placed under STP conditions.

<h3>What is an ideal gas equation?</h3>

The ideal gas law (PV = nRT) relates to the macroscopic properties of ideal gases. An ideal gas is a gas in which the particles (a) do not attract or repel one another and (b) take up no space (have no volume).

The solubility of methane in water at 25 degrees Celcius is 1.3 x $10^{ -3}$ M. It implies 1.3 x $10^{ -3}$ moles of methane are dissolved in one litre of water.

The number of moles of methane in 4 L of water can be calculated as follows:

Moles of methane = $\frac{1.3 . 10^{ -3} }{1L}$ x $\frac{4L}{1L}$

Moles of methane = 5.2 x $10^{ -3}$

STP refers to standard temperature and pressure. Under STP conditions, the temperature of the substance is 0 degrees celcius and its pressure is 1 atm.

An ideal gas is an imaginary gas comprising of a large number of randomly moving particles and the motion between such articles is considered to be perfectly elastic. The ideal gas equation describes the relationship between pressure, volume, temperature and number of moles of a gas.

The expression for ideal gas equation is as follows:

PV=nRT, where n is the moles and R is the gas constant. Then divide the given mass by the number of moles to get molar mass.

Given data:

P= 1 atm

V= ?

R= $0.082057338 \;L \;atm \;K^{-1}mol^{-1}$

T=273K

n=?

Putting value in the given equation:

$\frac{PV}{RT}=n$

5.2 x $10^{ -3} = \frac{1 \;atm\; X \;V}{0.082057338 \;L \;atm \;K^{-1}mol^{-1} X 273}$

V= 116.6 x $10^{ -3}$

Hence, 116.6 x $10^{ -3$ } is the volume of methane contained in 2.50 L of a saturated solution at 25 ∘C was extracted and placed under STP conditions.

Learn more about the ideal gas here:

brainly.com/question/27691721

#SPJ1

4 0

2 years ago

A compound with the empirical formula ch2 has a molar mass of 98 g/mol what is the molecular formula for this compound ?

madam [21]

Approximate molecular masses:
Molecular mass of C = 12
Molecular mass of H = 1

Let n = moles required for CH₂.
Then
nCH₂ = 98
n(12 + 2*1) = 98
14n = 98
n = 7

Answer: The molecular formula is 7CH₂

7 0

3 years ago

What is the kinetic energy of the emitted electrons when cesium is exposed to UV rays of frequency 1.3×1015Hz?

Sonja [21]

Answer:

We know that

ħf = ф + Ekmax

where

ħ = planks constant = 6.626x10^-34 J s

f = frequency of incident light = 1.3x10^15 /s (1 Hz =

1/s)

ф = work function of the cesium = 2.14 eV

Ekmax = max kinetic energy of the emmitted electron.

We distinguish that:

1 eV = 1.602x10^-19 J

So:

2.14 eV x (1.602x10^-19 J / 1 eV) = 3.428x10^-19 J

So,

Ekmax = (6.626x10^-34 J s) x (1.3x10^15 / s) - 3.428x10^-19 J

= 8.6138x10^-19 J - 3.428x10^-19 J = 5.1858x10^-19 J

Answer:

5.19x10^-19 J

Kinetic energy:

In physics, the kinetic energy of an object is the energy that it owns due to its motion. It is defined as the work required accelerating a body of a given mass from rest to its specified velocity. Having expanded this energy during its acceleration, the body upholds this kinetic energy lest its speed changes.

Answer details:

Subject: Chemistry

Level: College

Keywords:

• Energy

• Kinetic energy

• Kinetic energy of emitted electrons

Learn more to evaluate:

brainly.com/question/4997492

brainly.com/question/4010464

brainly.com/question/1754173

6 0

4 years ago

Read 2 more answers