Answer:
Knowing this, researchers from the University of Southern Denmark decided to investigate the size of these hypothetical hidden particles. According to the team, dark matter could weigh more than 10 billion billion (10^9) times more than a proton.
Explanation:
If this is true, a single dark matter particle could weigh about 1 microgram, which is about one-third the mass of a human cell (a typical human cell weighs about 3.5 micrograms), and right under the threshold for a particle to become a black hole.
a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction.
Answer:
The first one is B and the second one is A
Explanation:
Answer:
c = 4016.64 j/g.°C
Explanation:
Given data:
Mass of substance = 2.50 g
Calories release = 12 cal (12 ×4184 = 50208 j)
Initial temperature = 25°C
Final temperature = 20°C
Specific heat of substance = ?
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
Solution:
Q = m.c. ΔT
ΔT = T2 - T1
ΔT = 20°C - 25°C
ΔT = -5°C
50208 j = 2.50 g . c. -5°C
50208 j = -12.5 g.°C .c
50208 j /-12.5 g.°C = c
c = 4016.64 j/g.°C