Answer:
0.38 moles He
Explanation:
from the ideal gas law PV= nRT you can calculate the volume of 1 mole at STP (273..1K and 1 atm of pressure) the MOLAR VOLUME IS
22.4 L
In the problem you have 8.4L
8.4 L/22.4 L=0.375 moles
so
0.38 moles He
Answer:
0.934J/g°C
Explanation:
Using Q = mc∆T
However, in this question;
(Q)water = -(Q)metal
(mc∆T)water = -(mc∆T)metal
According to the information provided in the question;
For water;
m = mass = 72.9g
c = specific capacity of water = 4.184 J/g°C
∆T = 22.9 - 15.9 = 7°C
For metal;
m = mass = 45.7g
c = specific capacity of water = ?
∆T = 22.9 - 72.9 = -50°C
(mc∆T)water = -(mc∆T)metal
(72.9 × 4.184 × 7) = -(45.7 × c × -50)
2135.0952 = -(-2285c)
2135.0952 = 2285c
c = 2135.0952/2285
c of metal = 0.934J/g°C
Answer:
Atomic Number: 1
Atomic Mass: 1
Explanation:
Atomic number = # of protons
Atomic mass = # of protons + # of neutrons