Rafiq has heard that continued exposure to light for 10 days can change the colour of some blue dyes used to colour cotton clothing. He decides to test this. He takes a piece of clothing dyed with a blue dye which is suspected to lose colour on such exposure. He cuts the cloth into two pieces.

Which experiment is likely to help him conclude if the dye indeed can change colour?
He should expose, for 10 days-

A. Both pieces under 2 identical lamps.
B. One piece under a lamp; keep the other in darkness.
C. One piece for 5 days and one for 10 days under identical lamps
D. One piece folded and one piece spread out under 2 identical lamps.

The number of hours required : 37.2 hours

Given

⁴²K (potassium -42)

Required

The number of hours

Solution

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.  

Usually, radioactive elements have an unstable atomic nucleus.  

Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours

For three half-life periods :

[tex]\tt 3\times 12.4=37.2~hours[/tex]

Answer:

the noble gases

Answer:

30,000,000,000 Hz

Explanation:

I searched it up and got 3 x 10^10 and thats 30000000000

Answer:  Edgy, 2020

Explanation:    <3

Answer:

refer to picture below :)

Explanation:

Answer:

D. ocean ridges​

Explanation:

Answer:

I think A

Explanation:

Most volcanoes form at the boundaries of Earth's tectonic plates. ... The two types of plate boundaries that are most likely to produce volcanic activity are divergent plate boundaries and convergent plate boundaries

Answer:

C4H8O4

Explanation:

Let (CH20)x

C=1*12.01=12.01     (12.01, 1.01, 16.00 Avg mass of elements)

H=2*1.01=2.01

O=1*16.00=16.00

12.01 + 2.01 + 16.00 = 30.03

120.12/30,03=4

==> (CH2O)4 = C4H8O4

The molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex] is equal to [tex]C_4H_8O_4[/tex].

Given the following data:

Scientific data:

To determine the molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex]:

First of all, we would find the molar mass of [tex]CH_2O[/tex]:

[tex]CH_2O =12 +(1\times2)+16\\\\CH_2O =30\;g/mol[/tex]

For molecular formula:

[tex](CH_2O)n = 120.12\\\\30n = 120.12\\\\n=\frac{120.12}{30}[/tex]

n = 4.0

[tex](CH_2O)_4 = C_4H_8O_4[/tex]

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Answer:

Each names a given number of objects.

Explanation:

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 8 × 15

We have the final answer as

Hope this helps you

Answer:

question 2 is false

Explanation:

6 is D

Isotopes are atoms of the same element that have different numbers of neutrons. Protons are positively-charged particles found in the nucleus of an atom.

Electrons are negatively-charged particles found in the outer shell of an atom. The charge on an element is determined by the number of protons and electrons present in the atom.

a.) Li+:  number of protons = 3

Number of electrons = 2

charge of Li+ = +1

b.) Be2+: number of protons = 4

Number of electrons = 2

charge of Be2+ = 2+

c.) C4+: number of protons = 8

Number of electrons = 4

charge of C4+ = 4+

d.) O2-: number of protons = 8

Number of electrons = 10

charge of O2- = -2

e.) N3-: number of protons = 7

Number of electrons = 10

charge of N3- = -3

f.) C4- : number of protons = 4

Number of electrons = 4

charge of C4- = -4

g.) 14C6: The mass number = 14

Atomic number = 6

Number of neutrons = 8

h.) 18O8:  The mass number = 18

Atomic number = 8

Number of neutrons = 10

i.) 19F9:  The mass number = 19

Atomic number = 9

Number of neutrons = 10

j.) 40Ca20:  The mass number =40

Atomic number = 20

Number of neutrons = 20

k.) 37Cl17:  The mass number = 37

Atomic number = 17

Number of neutrons = 20

l.) 238U92:  The mass number = 238

Atomic number = 92

Number of neutrons = 146

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Answer:

PCl₅ = 208.22g/mol. UF₆ = 352.03g/mol.

Explanation:

Find the atomic mass of each element–and if there's a subscript (you multiply the atomic mass by that much). P= 30.97g, Cl= 35.45g; 30.97+35.45(5) = 208.22g [same idea with UF₆]

Answer:

b

Explanation:

Answer:

13 N to the right

Explanation:

Answer:

protons: 36

neutrons:48

electrons:36

Explanation:

the number of protons in an element is = to the atomic # (36)

the number of neutrons is the atomic mass - atomic # (84-36=48)

In a neutral charged element the # of protons = # of electrons

Answer:

Molecules are made of atoms. atoms are smaller. molecules have no electrons, atoms do.

Answer:

well one of the begins with and A while the other one begins with a M, joking so the difference between an atom and a molecules is that, An atom is the smallest unit of matter that retains all of the chemical properties of an element. while Molecules can be described as the smallest particle of an element or a compound, which is capable to exist independently and shows all the properties of the respective substance. Hope this helps :)

Explanation:

Answer:

(b) that is hydrophobic

Explanation:

e.g, alanine

Cause, Alanine possess hydrophobic side chain and the most appropriate answer is (d) part......

Alanine is an aliphatic amino acid, because the side-chain connected to the α-carbon atom is a methyl group (-CH3), alanine is the simplest α-amino acid after glycine. The methyl side-chain of alanine is non-reactive and is therefore hardly ever directly involved in protein function..

Hope it will help you☺☺☺☺☺

Answer:

(b) that is hydrophobic

Explanation:

e.g, alanine

Cause, Alanine possess hydrophobic side chain and the most appropriate answer is (d) part......

Alanine is an aliphatic amino acid, because the side-chain connected to the a-carbon atom is a methyl group (-CH3), alanine is the simplest a-amino acid after glycine. The methyl side-chain of alanine is non-reactive and is therefore hardly ever directly involved in protein function...

Hope it helps....

Answer:

Explanation:

The octet rule allows chemists to predict the placement of electrons around the nucleus (electron orbitals), the identification of electrons added or lost during chemical reactions and the chemical reactivity of atoms based upon their particular electron configuration.

Explanation:

Molar mass of Cobalt (II) chloride = 129.8g/mol

Moles of CoCl2 = 9.32/129.8 = 0.0718mol

Mass of H2O lost after heating = 15.80 - 9.32 = 6.48g

Moles of H2O = 6.48/18 = 0.36mol

Mole ratio of CoCl2 : H20

= 0.0718mol : 0.36mol

= 1 : 5

Hence the formula is CoCl2 . 5H2O, which is Copper (II) chloride pentahydrate.

Answer:

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question we have

[tex]a = \frac{5}{0.25} \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

The correct answer is V1/T1=V2/T2.

Explanation:

Just took the test

Answer:

Its A on edge :)

Explanation:

Answer:3 oxygen atoms.

Explanation: Each formula unit of Fe2O3 contains 2 atoms of iron and 3 atoms of oxygen (technically they are ions, but that doesn't matter).

Answer:

1)

Hg

80 protons, 80 electrons, 121 neutrons

2)

Mo

42 protons, 42 electrons, 54 neutrons

3)

Symbol is Cu, Mass is 64, 29 Protons

4)

C

Atomic number is 6, 6 protons, 6 electrons, 6 neutrons

5)

Symbol is P, 15 protons, 15 electrons, 16 neutrons

6)

Pb

Atomic number is 82, 82 electrons, 125 neutrons

7)

Na

Mass is 23, 11 protons, 11 electrons.

Hopefully this helps!

Answer:

CO2 has higher boiling point as compared to CO

Explanation:

Because CO is linear molecule anf zero dipole moment while CO2 is non linear and it has dipole moment

Answer:

B

Explanation:

Answer: has properties similar to other elements in group 18, does not react readily with other elements, is part of the noble gas group

Explanation: I’ve done on edg before

Answer:

c. Waxing crescent

- I hope this helps have a great night

Answer:

46 percent of trees have been cut down.

Scienctists helps plants, but humans do destroy a lot of plants.

Scientists - helps increase plant growth.

Woodchoppers - helps decrease plant growth.

Answer:

C

Explanation:

Element Z acquires two electrons from element X for stability