A hmogeneous mixture is i. same (uniform) throughout
ii. two or more substances that are combined
iii. same(uniform) chemicalproperties
throughout
iv. are sometimes called solutions
i, ii, iii
i, ii, iv
, iv
i, ii, iii, iv

step-by-step explanation:

whole numbers, zero or greater

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.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.