Answer:
3
Explanation:
In scientific notation, the number of integers in the first part will always be the amount of significant figures.
For example,
1) 1.542505 x 10^17 =7 significant figures
1) 1.54 x 10^17 =3 significant figures
Answer:
(A) The intermolecular attraction between HF molecules are stronger than between HCl molecules mainly to due hydrogen bonding.
Explanation:
Since Flourine is highly electronegative and as such, when it bonds with Hydrogen it forms a hydrogen bond. Whereas the HCL molecule is a polar molecule whose inter-molecular forces are dipole dipole interactions. Although a Hydrogen bond is a type of dipole dipole interaction it is stronger than the traditional dipole dipole forces and London dispersion forces. HF also has a shorter bond length which makes the bond and inter-molecular forces stronger as compared to HCL.
C. Chemical properties always change depending on temperature or pressure
Answer:
64799.4 J
Explanation:
The following data were obtained from the question:
Mass (M) = 1.05 kg = 1.05 x 1000 = 1050g
Specific heat capacity (C) = 0.9211 J/g°C
Initial temperature (T1) = 23°C
Final temperature (T2) = 90°C
Change in temperature (ΔT) = T2 – T1 =
90°C – 23°C = 67°C
Heat required (Q) =....?
The heat required to increase the temperature of the kettle can b obtain as follow:
Q = MCΔT
Q = 1050 x 0.9211 x 67
Q = 64799.4 J
Therefore, 64799.4 J of heat is required to increase th temperature of the kettle from 23°C to 90°C.
