Answer:
Helium is created from hydrogen in the sun's core.
Four hydrogen-1 nuclei fuse to produce
- one helium-4 nucleus, two neutrons,
- two positrons, and
- two electron neutrinos.
Explanation:
Step One:
.
Two hydrogen-1 nuclei fuse. One proton will convert to a neutron. The products will be
- one hydrogen-2 nucleus,
- one positron, and
- one electron neutrino.
Step Two:
.
There are plenty of hydrogen-1 nuclei available in the core of the sun. The hydrogen-2 nucleus from step one will fuse with a hydrogen-1 nucleus. The product is
Step Three
.
Two helium-3 nuclei from step two react with each other. The products are:
- one helium-4 nucleus, and
- two hydrogen-1 nuclei.
The overall reaction will be:
.
In other words, hydrogen nuclei in the core of the sun fuse together to form helium.
Answer:
V= 37.0 mL
Explanation:
First find the moles of the known substance (CuCl2)
n= cv
where
n is moles
c is concentration
v is volume ( in litres)
n= 0.108 × 0.0946
n=0.0102168
Using the mole ratio in the balanced reaction, we can find the moles of Na3PO4
n (Na3PO4)= n (CuCl2) × 2/3
=0.0102168 × 2/3
=0.0068112
Now we have all the necessary values to calculate the volume
v=n/c
v= 0.0068112/0.184
v= 0.0370173913 L
v= 37.0 mL
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Answer:
The hot tea should transfer <em>25.63 kJ</em> the surroundings to cool the tea.
Explanation:
- To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat has to be transferred from the tea to the surroundings to cool the tea (Q = ??? J).
m is the mass of the hot tea (m = dV = (1.0 g/mL)(250 mL) = 250 g), suppose the density of water is the density of tea.
c is the specific heat of the hot tea (c = 4.10 J/°C.g).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = 350 K - 375 K = -25°C).
<em>∴ Q = m.c.ΔT</em> = (250 g)(4.10 J/°C.g)(-25°C)) = <em>- 25630 J = - 25.63 kJ.</em>
<em>So, the hot tea should transfer 25.63 kJ the surroundings to cool the tea.</em>
