The formula is Al2O<span>3. 2 aluminium and 3 oxygen
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Taking into account the definition of calorimetry, the mass of the sample is 478.41 grams.
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is defined as the amount of heat that a body absorbs or releases without any changes in its physical state (phase change).
So, the equation that allows to calculate heat exchanges is:
Q = c× m× ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case, you know:
- Q= -543 J because the energy is releases
- c= 0.227
- m= ?
- ΔT= Tfinal - Tinitial= 10 C - 15 C= -5 C
Replacing:
-543 J= 0.227 × m× (-5 C)
Solving:
<u><em>m=478.41 grams</em></u>
In summary, the mass of the sample is 478.41 grams.
Learn more about calorimetry:
The right answer is C
Messenger RNA (mRNA) carries the genetic information copied from DNA in the form of a series of three-base code “words,” each of which specifies a particular amino acid. 2. Transfer RNA (tRNA) is the key to deciphering the code words in mRNA.
Answer: Option (b) is the correct answer.
Explanation:
When an atom is attached to another atom through sharing of electrons then bond formed between the atoms is known as a covalent bond. And, a bond formed by transfer of electrons from one atom to another is known as an ionic bond.
For example, electronic configuration of hydrogen is 
and electronic configuration of oxygen is 
. So, in order to attain stability hydrogen needs 1 more electron and an oxygen atom needs two electrons.
Therefore, two hydrogen atoms need to covalently bond through an oxygen atom leading to the formation of 
.
Thus, we can conclude that the electronegative oxygen that is central to a water molecule is covalently bound to two hydrogen atoms. These hydrogens are 'bent' to form a 
angle because four of the outer e- about oxygen are shared with hydrogens.
Answer: This is because of the different chemical composition of the types of detergents affects their cleansing actions.
Explanation:
Detergent means any substance which has the ability to clean an object. This includes soaps, soap powers and dish washing liquids as well as water. Detergents fall into two main types
--> Soapy detergents and
--> Soapless detergents
Soapy detergents are sodium salts of fatty acids. They are saponification products of fats and oils. In the chemical composition, each molecule of soap possesses a long hydrocarbon chain attached to an ionic head. The hydrocarbon tail is hydrophobic, so it is insoluble in water but soluble in oil and organic solvents. The ionic head is hydrophilic, so it is soluble in water. Due to this dual nature, when is dissolved in water, the soap molecule forms spherical clusters called MICELLES( hydrocarbon tails points inward and ionic heads point outward). Repulsion between the similarly charged ionic heads keeps the micelles apart. This property helps the soapy detergent to lift grease from grease coated fabrics when applied to it.
While the chemical properties of the Soapless detergents has a hydrophobic tail and a hydrophilic head. The hydrophobic tail is either a long chain hydrocarbon or a benzene ring with a long alkyl group attached. The hydrophilic head, unlike the Soapy detergents, can be positively or negatively charged or even neutral. These chemical properties makes it to have a more favourable and wider application than soapy detergent.it is suitable for washing acid - sensitive fabrics and for breaking up oil slicks.
