To answer, evaluate the power of 10 in the given choices. If it is positve, move the decimal n places to the right. If it is negative, move the decimal n corresponding places to the left. From all the choices given, only the choices D, E, and F will give us the correct answer.
Answer:
7.2g
Explanation:
From the expression of latent heat of steam, we have
Heat supplied by steam = Heat gain water + Heat gain by calorimeter
mathematically,
+ 
=
+
L=specific latent heat of water(steam)=2268J/g
=specific heat capacity=4.2J/gK
=specific heat capacity of calorimeter =0.9J/gk
=280g
=38g
α=change in temperature
=(40-25)=15
=(40-25)=15
=(100-40)=60
Note: the temperature of the calorimeter is the temperature of it content.
From the equation, we can make 
the subject of formula
Hence
Hence the amount of steam needed is 7.2g
<span>In Ionic type of bonding, electrons are lost (more
protons than electrons and positive charge) or gained (more electrons than
protons, still a negative charge) by atoms, and the atoms are held together by
electrical attraction in the process. Covalent bondings are the sharing of electrons
as well as partial bondings. Covalent bondings’ electrons have the same charges
thus, there is no gaining or losing electrons in the process of sharing. Strong
bondings are applicable only to Hydrogen (H) atoms. </span>
Answer:
1.7N
Explanation:
Force = kx
Where x = spring compression and
K = spring constant
K =85N/m
x = 2.0cm / 100
= 0.02m
Force = 85 x 0.02
= 1.7N
