1 Cal ---------- 4.184 J
? Cal ---------- 130.0 J
130.0 x 1 / 4.184 => 31.07 Cal
hope this helps!
        
             
        
        
        
So platinum is a transition metal. In general transition metals are reducers, which means they can give the electrons they have, to the sodium atoms. Also in chemistry we look at sub orbitals rather that shells(2,8,8). So due to the energy from heat, the d orbital split as electrons move to a higher energy level. Some of the electrons are given to the sodium ions and therefore the flame changes colour to yellow. 
The excitation of the electrons is caused by them getting energy and so moving up an energy level. This energy is released and the electron returns to it's original state. The energy released, however, does not release in the same direction, but in different/various directions. Therefore the colour of the light changes as some energy is released in the surrounding.
        
             
        
        
        
Given the following equation; Cu + 2AgNO3 = Cu(NO3)2 + 2Ag, 48.97 grams of Cu are needed to react with 262g of AgNO3.
<h3>How to calculate mass of substances?</h3>
The mass of a substance can be calculated using the following steps:
Cu + 2AgNO3 = Cu(NO3)2 + 2Ag
1 mole of Cu react with 2 moles of AgNO3
- Molar mass of AgNO3 = 169.87 g/mol
- Molar mass of Cu = 63.5g/mol
moles of AgNO3 = 262g/169.87g/mol = 1.54mol
1.54 moles of AgNO3 will react with 0.77 moles of Cu. 
mass of Cu = 0.77 × 63.5 = 48.97g
Therefore, given the following equation; Cu + 2AgNO3 = Cu(NO3)2 + 2Ag, 48.97 grams of Cu are needed to react with 262g of AgNO3.
Learn more about mass at: brainly.com/question/6876669
 
        
             
        
        
        
Answer:
Wet ashing is primarily used in the preparation of samples for subsequent analysis of specific minerals . It breaks down and removes the organic matrix surrounding the minerals so that they are left in an aqueous solution
Explanation: