Hello! Below is a program I wrote after a Chemistry lecture today. PV = nRT is an incredibly fundamental equation within Chemistry. Otherwise known as the Ideal Gas Law, this formula combines basis’ of Boyle’s Law, Charles’ Law, and Avangadro’s Law into a simple equation, which we can use to find any missing variables from the equation, when given the other circumstances.

### PV = nRT

P = pressure,

V = volume,

n = substance in moles,

R = 0.0821 (when unit is (atm*L)/(mol*K)) With other units, this constant will vary however, this is the constant used in this program, for these are the units used. Read more on this constant

T = temperature

The program I have written will take input from the user for the values they DO have, and use those to find the “mystery” value, whichever variable that may be.

// // main.cpp // PV=nRT // // Created by Aidan Takami on 2/22/18. // Copyright © 2018 Aidan Takami. All rights reserved. // #include using namespace std; void numbers(); double calculateP(); double calculateV(); double calculateN(); double calculateT(); //Fields double p, v, n, t; string pTemp = ""; string vTemp, nTemp, tTemp; bool keepGoing = true; const double R = 0.0821; //Main int main() { //Introduction & directions cout << "Hello! Welcome to the PV = nRT calculator! Type \"?\" for the value you are trying to find" << endl; while(keepGoing){ //Calls calculation method numbers(); } } //Method which gathers the numbers to be used in calculation void numbers(){ //Bool to represent whether mystery value has been found yet bool mysteryValue = false; //Bools to represent which value is mystery value bool pBool = false; bool vBool = false; bool nBool = false; bool tBool = false; //Used for continue/end process string temp; //Pressure cout << "What is the pressure in atm?" <> pTemp; //if the first value of the string is a digit if(isdigit(pTemp[0])){ //convert the string to a double p = stod(pTemp); } else{ pBool = true; mysteryValue = true; } //Volume cout << "What is the volume in L?" <> vTemp; //if the first value of the string is a digit if(isdigit(vTemp[0])){ //convert the string to a double v = stod(vTemp); } else if(mysteryValue == true){ //error message & restart cout << "We already have a mystery value! Let's try again!" << endl << endl; numbers(); } else{ vBool = true; mysteryValue = true; } //Moles cout << "What is the mole to molar mass ratio of the compound/element?" <> nTemp; //if the first value of the string is a digit if(isdigit(nTemp[0])){ //convert the string to a double n = stod(nTemp); } else if(mysteryValue == true){ //error message and restart cout << "We already have a mystery value! Let's try again!" << endl << endl; numbers(); } else{ nBool = true; mysteryValue = true; } //Temperature cout << "What is the temperature in Kelvin" <> tTemp; //if the first value of the string is a digit if(isdigit(tTemp[0])){ //convert the string to a double t = stod(tTemp); } else if(mysteryValue == true){ //error message and restart cout << "We already have a mystery value! Let's try again!" << endl << endl; numbers(); } else{ tBool = true; mysteryValue = true; } //if pressure = mystery value if(pBool){ cout << "The Pressure is: " << calculateP() << " atm!" << endl << endl; } //if volume = mystery value else if(vBool){ cout << "The Volume is: " << calculateV() << " L!" << endl << endl; } //if mole = mystery value else if(nBool){ cout << "The Molar Ratio is: " << calculateN() << " mol!" << endl << endl; } //if temp = mystery value else if(tBool){ cout << "The Temperature is: " << calculateT() << " K!" << endl << endl; } else{ cout << "You answered your own question! I cannot verify whether it's true or not.!" << endl; cout << "Try again!" << endl << endl << endl; } //Continue? cout << "Would you like to continue? (y/n)" <> temp; if(temp == "no" || temp == "n"){ keepGoing = false; } cout << endl; } //Calculates Pressure double calculateP(){ cout << (n * R * t) << endl; return (n*R*t)/v; } //Calculates Volume double calculateV(){ return (n*R*t)/p; } //Calculates Molar Ratio double calculateN(){ return (p*v)/(R*t); } //Calculates Temp double calculateT(){ return (p*v)/(R*n); }