I want to change the follow aktive sentence into passiv:

ordinary, or soft, solder melts at temperatures below 430°, but brazing alloys, sometimes called hard solder, melt above that temperature.

my solution:
temperatures below 430° are melted ordinary, or soft, solder, temperature above that is melted brazing alloys, sometimes called hard solder.

is it right?
I want to change the follow aktive sentence into passiv: ordinary, or soft, solder melts at temperatures below 430°, but ... are melted ordinary, or soft, solder, temperature above that is melted brazing alloys, sometimes called hard solder. is it right?

No. Should be.
ordinary, or soft, solder is melted at temperatures below 430°, but brazing alloys, sometimes called hard solder, are melted above that temperature.
John Ramsay schrieb:
I want to change the follow aktive sentence into passiv: ... melted brazing alloys, sometimes called hard solder. is it right?

No. Should be. ordinary, or soft, solder is melted at temperatures below 430°, but brazing alloys, sometimes called hard solder, are melted above that temperature.

The passive structure sounds strange to me - after all, it's the solder that melts.
Regards, Einde O'Callaghan
Students: We have free audio pronunciation exercises.
John Ramsay schrieb:

No. Should be. ordinary, or soft, solder is melted at temperatures below 430°, but brazing alloys, sometimes called hard solder, are melted above that temperature.

The passive structure sounds strange to me - after all, it's the solder that melts.

Or is melted by the application of heat, and the action of applying the heat is the melting.
Cookery books usually instruct: "melt the butter" not "make the butter melt".
I agree the passive is strange in the example, but test questions often bear little resemblance to Real Life(tm).
Owain
I want to change the follow aktive sentence into passiv: ordinary, or soft, solder melts at temperatures below 430=B0, but ... are melted ordinary, or soft, solder, temperatu=re above that is melted brazing alloys, sometimes called hard solder. is it right?

First, for an active sentence to be transformed into a passive sentence, there must be a direct object. The object of a preposition is not a direct object.
Second, as used in this sentence, the verb "melt" falls into a special category sometimes known as "ergative" verbs.
Other examples:
The ball rolled slowly down the hill.
The glass broke when it fell on the tile floor.
Most ships sink if they have a hole in the hull.
Karen