There may be other acceptable answers, but jet aircraft and atomic weaponry are the two which come immediately to mind.
Yes
Chemical weapons were first used in war by Germany in WW1.Nuclear weapons were first used in war by the US in WW2.
Weapons were used in battle during the civil war, at many battlefields in both North and South territory. The early forms of machine guns were used for the first time in the Civil War.
weapons/war
Atomic/nuclear weapons
Poison Gas Tanks Aeroplanes
Machine guns (automatic), tanks, poison gas, airplanes used for aerial combat were used in the military for the first time in WW I
Pikes, muskets, swords, pistols, cannons, mortars, lances. But for first time in history, firearms were used very heavily in war.
Tanks, aircraft, poison gas and the Dreadnought Battleship
the two most commonly used weapons were slingsgots and bombs
Some of the equipment used in the Battle of Somme in World War 1 was tanks and airplanes. This was unique as it was the first time these weapons had been significantly used in the war.
TankMachine GunMustard Chlorine GasHand GrenadeFighter Airplane