Answer:
The answer is: letter c, density.
Explanation:
Gold is a chemical element that is <em>very rare.</em> It has a high atomic number and is represented by the symbol "Au."
The problem above is asking about the physical property of gold that will help you determine whether a shiny gold nugget is, indeed, real gold. Remember that you are hiking and not anywhere else in the world.
If you look at choice a, appearance. This is definitely incorrect because looking at the object will not be able to help you verify whether it is true gold or "fool's gold." Considering melting point (letter b) would also be hard because you will be needing the necessary equipment to melt gold. Gold melts at 1,064 degrees Celsius. So,this sounds very impractical. (thus, melting point is incorrect) Now, if you look at letter d, physical state, it goes the same way with appearance. It will only tell you that the object is solid and that's it.
Letter c, density is the answer because if you analyze the density of gold, which is 19.32 grams per cubic meter, it is far from the density of iron pyrite (fool's gold) which is 4.8-5 grams per cubic meter. This means that gold is denser or heavier than iron pyrite. You will definitely be able to tell which such big gap in their densities.
Answer: trees compete for resources directly around them .
<u>Given data</u>
Determine Internal energy of gas N₂, (U) = ?
Temperature (T) = 25° C
= 25+273 = 298 K,
Gas constant (R) = 8.31 J/ mol-K ,
Number of moles (n) = 3 moles,
<u>Internal energy of N₂ </u>
Internal energy is a property of thermodynamics, the concept of internal energy can be understand by ideal gas. For example N₂, the observations for oxygen and nitrogen at atmospheric temperatures, f=5, (where f is translational degrees of freedom).
So per kilogram of gas,
The internal energy (U) = 5/2 .n.R.T
= (5/2) × 3 × 8.31 ×298
= 18572.85 J
<em>The internal energy of the N₂ is 18,572.85 J and it is approximately equal to 18,600 J given in the option B.</em>
Answer:
glutamate ,GABA
Explanation:
In the vertebrate central nervous system (CNS), glutamate serves as the major excitatory neurotransmitter, whereas GABA and glycine serve as the major inhibitory neurotransmitters.
Answer:
a)3000ohm
b)4.44mA
Explanation:
a) we were given a Nine tree lights connected inparallel across 120-V potential difference, since the resistor are in parallel we use the expresion below
1/R(total)= 1/R₁ + 1/R₂ + 1/R₃ + 1/R₃ +.... 1/R₉
But according to ohm'law which can be expressed below
V=IR
R=V/I
R(total)= 120/0.36
= 333.33ohm
1/R(total)= 1/R₁ + 1/R₂ + 1/R₃ + 1/R₃ +.... 1/R₉
R₁=R₂ =R₃ =R₄= R₅=R₆=R₇=R₈=R₉
1/R(total)=9/R
1/333.33= 9/R
R= 3000ohm
Therefore, the resistance is 3000ohm
b)the bulbs were connected in series here, then for series connection we use below expression
R₁=R₂ =R₃ =R₄= R₅=R₆=R₇=R₈=R₉
R(total)=9R
= 9*3000
=27000ohm
I=VR
I=V/R
I= 120/27000
= 4.44*10⁻³A
4.44mA
Therefore, the current is 4.4mA
