(pl , all i need is 3 substances ) substances that make up niobium ?

niobium and tantalum, oxide and manganese

Explanation:

Both niobium and tantalum are found together in the mineral columbite, a mixed oxide that also contains iron and manganese, and they have similar chemical and physical properties. In fact Niobium was originally named columbium after Columbia, because of its discovery in a mineral sent from America in 1801

question: ray weighs 100 kilograms, his wrestling partner, bobby, weighs 50 kilograms. if ray moves at 4 m s , how fast will bobby have to run at him to apply an equal amount of kinetic energy?

answer: 8 m/s he needs to run twice as fast to keep up so he has some work to do

explanation:   if the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

question answered by

(jacemorris04)

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.