Answer:
A & D
Explanation:
A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.
From the options, only options A & D fits this definition of single-displacement reactions.
For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.
For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.
The other options are not correct because they don't involve only and element and a compound on each side of the reaction.
Explanation:
0.566kg *(1mol/0.197 kg)= 2.87 mol gold
note how the units cancel out, if the units do not cancel out (kg/kg=1) then u did something wrong
Given:
Sample 1:
Chloroform is 
12 g Carbon
1.01 g Hydrogen
106.4 g Cl
Sample 2:
30.0 g of Carbon
Solution:
mass of chloroform from sample 1:
12 + 1.01 +106.4 =119.41 g
Now, for the total mass of chloroform in sample 2:
mass of chloroform 
mass of chloroform = 119.41 
= 298.53 g
Answer:
200 m\ s Ans .....
Explanation:
Data:
f = 200 Hz
w = 1.0 m
v = ?
Formula:
v = f w
Solution:
v = ( 200)(1.0)
v = 200 m\s <em>A</em><em>n</em><em>s</em><em> </em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em>
Answer:
The amount of energy is directly proportional to the photon's electromagnetic frequency and thus, equivalently, is inversely proportional to the wavelength. The higher the photon's frequency, the higher its energy.
i hope this helps.
Explanation:
