2.5X20=50g
50g should be the right answer
Mass=volumeXdenisty.
Answer:
Chemical reactions do not involve changes in the chemical bonds that join
atoms in compounds :
<u>False</u>
Explanation:
Chemical reaction are the reaction in which old bonds break and new bonds are formed . The formation of new bond result in formation of new compounds . This happen because new bond are result of linking different atoms by the bond.
For example : Water formation from Oxygen and Hydrogen is a chemical process :
Original(old) bonds are :
H-H bond in H2 and O-O bonds in O2
In H2 = Hydrogen is joined to Hydrogen
IN O2 = Oxygen is joined to oxygen
New Bonds =
O-H bonds in water (H2O)
Oxygen is joined to hydrogen = New Bond formation
Hence,
<u>Chemical reactions do involve changes in the chemical bonds that join
</u>
<u>atoms in compounds</u>
<u />
Don’t eat or drink in labs
Dress for the lab; don’t wear open toed shoes
Dispose of lab waste properly
No horse play
Don’t taste or sniff things in the lab
Tire your hair back
<h3><u>Answer;</u></h3>
<em>-49 °C</em>
<h3><u>Explanation and solution;</u></h3>
- Considering the fact that, the specific heat capacity of aluminum is 0.903 J/g x C, and the heat of vaporization of water at 25 C is 44.0 KJ/mol.
Moles water = 0.48 g / 18.02 g/mol
=0.0266 moles
<em>Heat lost by water</em> = 0.0266 mol x 44.0 kJ/mol
=1.17 kJ => 1170 J
<em>But heat lost =heat gained</em>
<em>Therefore;</em> Heat gained by aluminium = 1170 J
1170 = 55 x 0.903 ( T - 25) = 49.7 T - 1242
1170 + 1242 = 49.7 T
T = 48.5 °C ( 49 °C <em>at two significant figures)</em>
<em>Hence</em>, final temperature = 49 °C
Naming conventions for 2 non-metals like Si and O are based on their valence electrons, Si has 4 electrons around it and Oxygen has 6, in order for you to satisfy octet (8 electrons around each element) surrounding each Si and O, you need another O, To name these 2, just write the name of the first element which has less electrons first then the second element to which you use a prefix "di" since it means there are two oxygen, then put the names together and end the name of the second element with "ide" (remove the last 4 letters).
Silicon + "dI" + ox +"ide"
