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.
The smallest unit that can exist as an element and still have proprieties of that element is an Atom<span />
Answer:
a) A satellite is warmed by sunlight.
Explanation:
Heat transfer by radiation mostly involves heat gain or heat loss from the Sun. In this case, Option A is the only option where sunlight is involved so it is the best example of heat transfer by radiation.
Answer:
IO₂
Explanation:
We have been given the mass percentages of the elements that makes up the compound:
Mass percentage given are:
Iodine = 79.86%
Oxygen = 20.14%
To calculate the empirical formula which is the simplest formula of the compound, we follow these steps:
> Express the mass percentages as the mass of the elements of the compound.
> Find the number of moles by dividing through by the atomic masses
> Divide by the smallest and either approximate to nearest whole number or multiply through by a factor.
> The ratio is the empirical formula of the compound.
Solution:
I O
% of elements 79.86 20.14
Mass (in g) 79.86 20.14
Moles(divide by
Atomic mass) 79.86/127 20.14/16
Moles 0.634 1.259
Dividing by
Smallest 0.634/0.634 1.259/0.634
1 2
The empirical formula is IO₂
