The heat for melting or freezing water, also called the Heat of Fusion (Hf), is 80 calories per gram at 0Â°C, which is the equilibrium temperature. In other words, it is necessary to add 80 calories of energy to melt one gram of ice at 0Â°C.
The CVV Number (Card Verification Value) on your credit card or debit card is a 3 digit number on VISAÂ®, MasterCardÂ® and DiscoverÂ® branded credit and debit cards. On your American ExpressÂ® branded credit or debit card it is a 4 digit numeric code.
1 American Express cards have a four-digit code printed on the front side of the card above the number.  Diners Club, Discover, JCB, MasterCard, and Visa credit and debit cards cvv no open security code have a three-digit card security code.