In the presence of a strong acid, litmus paper exhibits a(n) ________________

Sergeu [11.5K]

Answer:

memory cells

Explanation:

The unscrambled words are white blood cells, memory cells, and antibodies. Memory cells is the correct answer, so that's what you'd write.

4 0

4 years ago

I need help asap thank u

UNO [17]

It is b, i learned this last year hope this helps

4 0

3 years ago

In which technique atomic absorption or atomic emission is flame temperature stability more critical?

Fittoniya [83]

Atomic emission
There are two broad methods of using atomic spectroscopy to identify the elements present and their quantities. That being atomic absorption where light of a known wavelength is absorbed by atoms suspended within a flame and atomic emission where the atoms are excited by energy and emit light of known wavelengths that can then be measured.
For atomic absorption to work, the main criteria is that the atoms be evenly dispersed throughout the flame and that they not be excited enough to spontaneously emit light themselves. As such a rather wide range of flame temperatures is acceptable and will cause only minor variations on the amount of absorbed light.
For atomic emission to work, the flame needs to be hot enough to excite the atoms into spontaneously emit their characteristic wavelengths. Additionally, increasing the temperature will cause more light to be emitted even if the concentration of the atoms remains the same. So stable temperature control is vital for accurate measurements.

4 0

3 years ago

1. Determine the molecular formula of an oxide of iron in which the mass of iron and oxygen are 69.9% and 30% respectively given

Scorpion4ik [409]

1a. The empirical formula of the compound is Fe₂O₃

1b. The molecular formula of the compound is Fe₂O₃

2a. The molecular formula of the anhydrous salt is MgSO₄

2b. The formula of the crystalline salt is MgSO₄.7H₂O

3i. The number of mole of carbon atoms in the compound is 6 moles

3ii. The number of mole of hydrogen atoms in the compound is 18 moles

3iii. The number of molecules in 3 moles of ethane is 1.806×10²⁴ molecules

<h3>1a. How to determine the empirical formula</h3>

Fe = 69.9%
O = 30%
Empirical formula =?

Divide by their molar mass

Fe = 69.9 / 56 = 1.248

O = 30 / 16 = 1.875

Divide by the smallest

Fe = 1.248 / 1.248 = 1

O = 1.875 / 1.248 = 3/2

Multiply by 2 to express in whole number

Fe = 1 × 2 = 2

O = 3/2 × 2 = 3

Thus, the empirical formula of the compound is Fe₂O₃

<h3>1b. How to determine the molecular formula</h3>

Empirical formula = Fe₂O₃
Molar mass of compound = 159.89 g/mol
Molecular formula = ?

Molecular formula = empirical × n = molar mass

[Fe₂O₃]n = 159.89

[(56×2) + (16×3)]n = 159.89

160n = 159.89

n = 159.89 / 160

n = 1

Molecular formula = [Fe₂O₃]n

Molecular formula = [Fe₂O₃] × 1

Molecular formula = Fe₂O₃

<h3>2a. How to determine the molecual formula of the anhydrous salt</h3>

We'll begin by calculating the empirical formula

Mg = 20.0%
S = 26.66%
O = 53.33%
Empirical formula =?

Divide by their molar mass

Mg = 20.0 / 24 = 0.83

S = 26.66 / 32 = 0.83

O = 53.33 / 16 = 3.33

Divide by the smallest

Mg = 0.83 / 0.83 = 1

S = 0.83 / 0.83 = 1

O = 3.33 / 0.83 = 4

Thus, the empirical formula of the anhydrous salt is MgSO₄

The molecular formula of the anhydrous salt can be obtained as follow:

Empirical formula = MgSO₄
Molar mass of compound = 120 g/mol
Molecular formula = ?

Molecular formula = empirical × n = molar mass

[MgSO₄]n = 120

[24 + 32 + (16×4)]n = 159.89

120n = 120

n = 120 / 120

n = 1

Molecular formula = [MgSO₄]n

Molecular formula = [MgSO₄] × 1

Molecular formula = MgSO₄

<h3>2b. How to determine the formula of the crystalline salt</h3>

Water (H₂O) = 51.2%
Anhydrous salt (MgSO₄) = 100 - 51.2 = 48.8%
Formula of crystalline salt =?

Divide by their molar mass

MgSO₄ = 48.8 / 120 = 0.4

H₂O = 51.2 / 18 = 2.8

Divide by the smallest

MgSO₄ = 0.4 / 0.4 = 1

H₂O = 2.8 / 0.4 = 7

Thus, the formula of the crystalline salt is MgSO₄.7H₂O

<h3>3i. How to determine the mole of carbon atoms in 3 moles of C₂H₆</h3>

1 mole of C₂H₆ contains 2 moles of carbon atoms.

Therefore,

3 moles of C₂H₆ will contain = 3 × 2 = 6 moles of carbon atoms

<h3>3ii. How to determine the mole of hydrogen atoms in 3 moles of C₂H₆</h3>

1 mole of C₂H₆ contains 6 moles of hydrogen atoms.

Therefore,

3 moles of C₂H₆ will contain = 3 × 6 = 18 moles of hydrogen atoms

<h3>3iii. How to determine the number of molecules</h3>

From Avogadro's hypothesis,

1 mole of ethane = 6.02×10²³ molecules

Therefore,

3 moles of ethane = 3 × 6.02×10²³ molecules

3 moles of ethane = 1.806×10²⁴ molecules

Learn more about empirical formula:

brainly.com/question/24297883

Learn more about Avogadro's number:

brainly.com/question/26141731

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Complete question

2. A crystalline salt when heated becomes anhydrous and loses 51.2% of its weight the anhydrous salt analysis gave the percent composition as magnesium is equal to 20.0% and sulphur is equal to 26.66% and oxygen is equal to 53.33%. Ccalculate the molecular formula of the anhydrous and the crystalline salt. The molecular weight of the anhydrous salt is 120

4 0

2 years ago

How are the functions of ribosome, Golgi bodies, and endoplasmic related?

mihalych1998 [28]

all 3 are related to each other through their involvement in protein synthesis and transport.

Ribosomes are the sites of protein synthesis and carry out this work by assembling the amino acids in the appropriate sequence, as dictated by the mRNA (messenger RNA).

These cell organelles are most commonly found embedded in the endoplasmic reticulum. Large scale protein synthesis is possible due to the very large surface area offered by the endoplasmic reticulum to the ribosomes.

The main function of the endoplasmic reticulum is to transport the newly synthesized proteins over to the Golgi apparatus. The primary role of the Golgi apparatus is to modify the proteins and encase them into vesicles. From here they are transported to the various parts of the cell.

this is why it's the answer!

5 0

4 years ago

In the presence of a strong acid, litmus paper exhibits a(n) _________________ color.