Answer:
Think it's NC13
Explanation:
It's the only one missing in the molecule
Answer:

Explanation:
<u>1. Convert Grams to Moles</u>
Use the molar mass (found on the Periodic Table) to convert from grams to moles.
Use this value as a ratio.

Multiply by the given number of grams.

Flip the ratio so the grams of boron cancel out.



<u>2. Convert Moles to Atoms</u>
We use Avogadro's Number, 6.02*10²³: the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of boron.

Multiply by the number of moles we calculated.

The moles of boron cancel.


The original value of grams has 4 significant figures, so our answer should have the same. For the number we calculated, that is the thousandth place.

The 6 tells us to round the 2 to a 3.

25.00 grams of boron is equal to 1.393*10²⁴ atoms.
Answer:
Q = 693 J
Explanation:
NaCl (aq) + AgNO₃ (aq) → AgCl (s) + NaNO₃ (aq)
Q = mcΔT
Q: heat
m: mass
c: specific heat
ΔT: temperature variation
Q = (50.0g + 100.0g) x (4.20 J/g°C) x (25.2°C - 24.1°C)
Q = 693 J