Answer:
When copper(II) chloride and sodium carbonate solutions are combined, solid copper(II) carbonate precipitates, leaving a solution of sodium chloride. Write the conventional equation, total ionic equation, and net ionic equation for this reaction. 
Explanation:
The word equation for the reaction is:
Copper (II) chloride(aq) + sodium carbonate (aq) ->sodium chloride (aq) +           copper carbonate(s)
The balanced chemical equation of the reaction is:

The complete ionic equation is:

The net ionic equation is obtained from the complete ionic equation after removing the spectator ions:

 
        
             
        
        
        
To solve this problem, we must assume ideal gas behaviour so
that we can use Graham’s law:
vA / vB = sqrt (MW_B / MW_A)
where,
<span>vA = speed of diffusion of A  (HBR)</span>
vB = speed of diffusion of B (unknown)
MW_B = molecular weight of B (unkown)
MW_A = molar weight of HBr = 80.91 amu
 
We know from the given that:
vA / vB = 1 / 1.49
 
So,
1/1.49 = sqrt (MW_B / 80.91)
MW_B = 36.44 g/mol
 
Since this unknown is also hydrogen halide, therefore this
must be in the form of HX.
HX = 36.44 g/mol , therefore:
x = 35.44 g/mol
 
From the Periodic Table, Chlorine (Cl) has a molar mass of
35.44 g/mol. Therefore the hydrogen halide is:
HCl
 
        
             
        
        
        
The melting point of potassium = 
Melting point of titanium = 
Titanium has a stronger metallic bonding compared to potassium. Titanium being a transition metal has greater number of valence electrons (4 valence electrons) contributing to the valence electron sea compared to potassium which has only one valence electron. The atomic size of Titanium much lower than that of potassium, so the bonding between Titanium atoms is stronger than that of potassium. Hence, the melting point of Titanium is much higher than that of potassium.
 
        
             
        
        
        
The answer is D :) have a nice day!
        
                    
             
        
        
        
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.