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3 years ago

Bacteria have a nucleus but no nuclear membrane * True False

Chemistry

1 answer:

serious [3.7K]3 years ago

7 0

Answer:

Explanation:

Bacteria are prokaryotic cells. They do not have a nuclear membrane and chloroplast is also absent. In photosynthetic bacteria, there are lamellae called thylakoids which contain enzymes and bacterial chlorophyll necessary for photosynthesis.

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Use the following equation to determine the charge on iron when it dissociates from oxygen and determine whether it is being oxi

kumpel [21]

The correct answer is A. Brainliest would be much appreciated.

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3 years ago

C3Hs + O2 = Co2 +H20

telo118 [61]

Answer:

algabra

Explanation:

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3 years ago

How many joules of heat are absorbed when 1000g of water is heated from 18Celsius to 85celsius?

o-na [289]

Answer + Explanations

Calculate heat absorption using the formula:

Q = mc∆T

Q means the heat absorbed, m is the mass of the substance absorbing heat, c is the specific heat capacity and ∆T is the change in temperature.

The heat absorbed is calculated by using the specific heat of water and the equation ΔH=cp×m×ΔT. 4. Water is vaporized to steam at 100oC. The heat absorbed is calculated by multiplying the moles of water by the molar heat of vaporization.

You can do this easily: just multiply the heat capacity of the substance you're heating by the mass of the substance and the change in temperature to find the heat absorbed.

To calculate the amount of heat released in a chemical reaction, use the equation Q = mc ΔT, where Q is the heat energy transferred (in joules), m is the mass of the liquid being heated (in kilograms), c is the specific heat capacity of the liquid (joule per kilogram degrees Celsius), and ΔT is the change in ...

Q = mc∆T. Q = heat energy (Joules, J) m = mass of a substance (kg) c = specific heat (units J/kg∙K) ∆ is a symbol meaning "the change in"

Precisely, water has to absorb 4,184 Joules of heat (1 calorie) for the temperature of one kilogram of water to increase 1°C. For comparison sake, it only takes 385 Joules of heat to raise 1 kilogram of copper 1°C.

A reaction that absorbs heat is endothermic. Its enthalpy will be positive, and it will cool down its surroundings. This reaction is exothermic (negative enthalpy, release of heat).

Quantitative experiments show that 4.18 Joules of heat energy are required to raise the temperature of 1g of water by 1°C. Thus, a liter (1000g) of water that increased from 24 to 25°C has absorbed 4.18 J/g°C x 1000g x 1°C or 4180 Joules of energy.

6 0

3 years ago

Give the chemical symbol of an element in the third period (row) of the periodic table with four 3p electrons.

Ann [662]

<u>Answer: </u>The chemical symbol of the element is Sulfur.

<u>Explanation:</u>

The element which is present in third period of the periodic table having four 3p electrons is Sulfur. Sulfur is the 16th element of the periodic table which has 6 valance electrons.

The electronic configuration of this element is: $[Ne]3s^23p^4$

This element is considered as a non-metal because it will accept electrons in order to attain stable electronic configuration.

Hence, the chemical symbol of the element is Sulfur.

7 0

3 years ago

Draw the best Lewis structure for CH 3 -1. What is the formal charge on the C?

djyliett [7]

Answer : The formal charge on the C is, (-1) charge.

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $CH_3^{-1}$

As we know that carbon has '4' valence electrons and hydrogen has '1' valence electron.

Therefore, the total number of valence electrons in $CH_3^{-1}$ = 4 + 3(1) + 1 = 8

According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.

Now we have to determine the formal charge on carbon atom.

Formula for formal charge :

$\text{Formal charge}=\text{Valence electrons}-\text{Non-bonding electrons}-\frac{\text{Bonding electrons}}{2}$

$\text{Formal charge on C}=4-2-\frac{6}{2}=-1$

The formal charge on the C is, (-1) charge.

3 0

3 years ago