What is a good song for a soprano to sing for an audition to show range?

That would depend on just how high you want your voice to go. Mariah Carey has some great songs but it may come off like you are shouting so be careful picking her. You might want to try something like the songs from Mamma Mia. I personally like the song "I have a dream" from that movie. It starts off low and goes into high pitch (plus it's a beautiful song). Good luck.

Hmm, there's not much for range in terms of sopranos for musical theater. I might suggest "And This is My Beloved" from Kismet because it shows off the high range but also has some good mid-to low-range stuff in it, too. Depending on the show, you may want to sing something less contemporary (or more so). Pop songs don't tend to be good audition songs, so I advise against those.

All the Things You Are is great. Listen to this version from the original show. (The sheet music is a step or half step lower.)

These are great FEMALE SOLOS for auditions A BRAND NEW DRESS... Coco A FOGGY DAY IN LONDON TOWN. Dmsel in Distres A JOURNEY TO A STAR.. The Gang's all Here A LADY OF SENSIBILITY.. Lady Pirates of capt. Bree A NEW LIFE... Jekyll and Hyde A WHOLE LOTTA SUNLIGHT... Raisin ACID QUEEN.. The Who's Tommy ALL MY LOVIN'... Across the Universe ALMOST LIKE BEING IN LOVE.. Brigadoon ANOTHER HUNDRED PEOPLE.. Company APPLAUSE... Applause BACK TO BASE... Closer than Ever BACK TO BEFORE.. Ragtime BACKWOODS BARBIE.. 9 to 5 BE MY HOST.. Fanny BE ON YOUR OWN... Nine BEFORE I KISS THE WORLD GOODBYE.. Jennie BIG SPENDER... Sweet Charity BLESS THE LORD.. Can Do BOUNCE ME BROTHER.. Swing BREATH... In the Heights BUENOS AIRES... Evita CAFÉ CONTINENTAL... Big CANDLE IN THE WATER.. Pete's Dragon CABARET.. Cabaret C'EST MAGNAFIQUE... Can Can COLORED WOMAN... Memphis DANCE 10, LOOKS 3... A Chorus Line DAY BY DAY.. Godspell DIVA'S LAMENT.. Spam DON'T STOP BELIEVIN.. Rock of Ages EASY TERMS.. Blood Brothers EASY TO BE HARD.. Hair ESCAPE... Escape EVERYTHING ELSE.. Next to Normal FALLING IN LOVE WITH LOVE.. Boys from Syracuse FEELINGS YOU'VE GOT TO HIDE... Sideshow FIFTY PERCENT.. Ballroom FLY ME TO THE MOON.. Come Fly Away FOLLOW YOUR HEART... Urintown GIMME LOVE.. Kiss of the Spider Woman GLITTER AND BE GAY ... Candide GREEN FINCH AND LINET BIRD.. Sweeney todd GRAND AVENUE... Flower Drum Song GRIZABELLA THE GLAMOUR CAT... Cats GROWING UP CATHOLIC.. Nonsense HAIL THE HAPPY COUPLE... Pardon my English HAPPY EASTER... Easter Parade HELL NO.. The Color Purple HOLDING ON.. Secret Garden HOLDING TO THE GROUND... Falsettoland HONEY, HONEY.. Momma Mia TEACHER DON'T TEACH ME NO NONSENSE... Race HOW LUCKY CAN YOU GET.. Funny Lady I AIN'T GOT TIME.. Zanna Don't I DON'T KNOW HIS NAME... She Likes Me I GOT RHYTHM... Girl Crazy I HAD A BALL... I had a ball I HATE MUSICALS... Ruthless I KEEP REMEMBERING YOU... Yank I LIKE THE LOOK OF LOVE... Oh Calcutta I LOVE YOU PORGY... Porgy and Bewss I MIGHT GROW FOND OF YOU.. Sunny I NEVER SAID I LOVE YOU... Dear World I WANT IT ALL.. Baby I WAS WAY AHEAD AND SEESAW.. Seesaw IF MOMMA WERE MARRIED... Gypsy I'M A WOMAN... Smokey Joe's Café INSIDE YOUR HEART.. Bad Boy IT MIGHT AS WELL BE SPRING... State Fair\ IT WON'T LET US LEAVE... Evil Dead IT'S A LOVELY DAY... Call me Madam JUST AROUND THE RIVER BEND.. Pocahontas IT'S NEVER ENTERED MY MIND..Higher and Higher JUST WILD ABOUT HARRY.. Big Deal KEYS .. Passing Strange LADY'S MAID... Titanic LAY DOWN YOUR HEAD.. Violet LIGHT... The Adventures of Tom Sawyer LOOK FOR A SILVER LINING. Till the Clouds roll by LOOK TO THE RAINBOW... Finian's Rainbow LOSING MY MIND.. Fossee LOVE... Love me Tonight LOVE MAKES THE WORLD GO ROUND.. Carnival LOVE NEVER DIES... Love Never Dies LOVE'S NEVER EASY... Bombay Dreams LULLABY OF BROADWAY... 42nd Street MACAROONS... Acorn Antiques MELTING MOGGY... Honk MISTER RIGHT... Love Life MOLL'S SONG... The Cradle Will Rock MY FUNNY VALENTINE... Babes in Arms MY OWN MORNING... Halleelujah Baby NINE PEOPLE'S FAVORITE THING.. Title of Show NO OTHER LOVE.. Me and Juliet NOBODY'S SIDE... Chess NOT SINCE NINEVEH... Kismet 100 WAYS TO LOSE A MAN.. Wonderful Town OOH! MY FEET... The most happy fella ONCE UPON A DECEMBER.... Anastasia\ ONE DAY I'LL FLY AWAY.. Moulin Rouge ONE NIGHT ONLY.. Dream Girls PARIS BY NIGHT.. Victor Victoria PASSONATE and TRUE..The Addams Family MUsical. PURLIE... Purlie RAGS... Rags RAIN ON THE ROOF.. The Wild Party ROLL IN THE HAY.. The Young Frankenstein SECOND STAR TO THE RIGHT... Peter Pan SHINE... Billy Elliot SEPTEMBER SONG... Lovemusik SOME DAY.. The Wedding Singer T'AINT NOBODY'S BUSINESS.. Black and Blue THANK GOD I'M OLD... Barnum THE BARE NECESSITIES... The Jungle Book THE CALLING.. Altar Boyz THE GARDEN RAM... Two by Two THE MAN I LOVE.. Strike up the Band TO KEEP MY LOVE ALIVE.. Connecticut Yankee TOO MANY RINGS AROUND ROSIE.. No, No Nanette UNDER THE TREE.. Celebration YOU TOOK ADVANTAGE of me.. On Your Toes WAITING FOR LIFE...Once upon this Island WITH ONE LOOK.. Sunset Boulevard WORDS, WORDS, WORDS.. Witches of Eastwick YOU'LL NEVER BE ALONE.A Tale of Two Cities

Hmm, there's not much for range in terms of sopranos for musical theater. I might suggest "And This is My Beloved" from Kismet because it shows off the high range but also has some good mid-to low-range stuff in it, too. Depending on the show, you may want to sing something less contemporary (or more so). Pop songs don't tend to be good audition songs, so I advise against those.

These are great FEMALE SOLOS for auditions A BRAND NEW DRESS... Coco A FOGGY DAY IN LONDON TOWN. Dmsel in Distres A JOURNEY TO A STAR.. The Gang's all Here A LADY OF SENSIBILITY.. Lady Pirates of capt. Bree A NEW LIFE... Jekyll and Hyde A WHOLE LOTTA SUNLIGHT... Raisin ACID QUEEN.. The Who's Tommy ALL MY LOVIN'... Across the Universe ALMOST LIKE BEING IN LOVE.. Brigadoon ANOTHER HUNDRED PEOPLE.. Company APPLAUSE... Applause BACK TO BASE... Closer than Ever BACK TO BEFORE.. Ragtime BACKWOODS BARBIE.. 9 to 5 BE MY HOST.. Fanny BE ON YOUR OWN... Nine BEFORE I KISS THE WORLD GOODBYE.. Jennie BIG SPENDER... Sweet Charity BLESS THE LORD.. Can Do BOUNCE ME BROTHER.. Swing BREATH... In the Heights BUENOS AIRES... Evita CAFÉ CONTINENTAL... Big CANDLE IN THE WATER.. Pete's Dragon CABARET.. Cabaret C'EST MAGNAFIQUE... Can Can COLORED WOMAN... Memphis DANCE 10, LOOKS 3... A Chorus Line DAY BY DAY.. Godspell DIVA'S LAMENT.. Spam DON'T STOP BELIEVIN.. Rock of Ages EASY TERMS.. Blood Brothers EASY TO BE HARD.. Hair ESCAPE... Escape EVERYTHING ELSE.. Next to Normal FALLING IN LOVE WITH LOVE.. Boys from Syracuse FEELINGS YOU'VE GOT TO HIDE... Sideshow FIFTY PERCENT.. Ballroom FLY ME TO THE MOON.. Come Fly Away FOLLOW YOUR HEART... Urintown GIMME LOVE.. Kiss of the Spider Woman GLITTER AND BE GAY ... Candide GREEN FINCH AND LINET BIRD.. Sweeney todd GRAND AVENUE... Flower Drum Song GRIZABELLA THE GLAMOUR CAT... Cats GROWING UP CATHOLIC.. Nonsense HAIL THE HAPPY COUPLE... Pardon my English HAPPY EASTER... Easter Parade HELL NO.. The Color Purple HOLDING ON.. Secret Garden HOLDING TO THE GROUND... Falsettoland HONEY, HONEY.. Momma Mia TEACHER DON'T TEACH ME NO NONSENSE... Race HOW LUCKY CAN YOU GET.. Funny Lady I AIN'T GOT TIME.. Zanna Don't I DON'T KNOW HIS NAME... She Likes Me I GOT RHYTHM... Girl Crazy I HAD A BALL... I had a ball I HATE MUSICALS... Ruthless I KEEP REMEMBERING YOU... Yank I LIKE THE LOOK OF LOVE... Oh Calcutta I LOVE YOU PORGY... Porgy and Bewss I MIGHT GROW FOND OF YOU.. Sunny I NEVER SAID I LOVE YOU... Dear World I WANT IT ALL.. Baby I WAS WAY AHEAD AND SEESAW.. Seesaw IF MOMMA WERE MARRIED... Gypsy I'M A WOMAN... Smokey Joe's Café INSIDE YOUR HEART.. Bad Boy IT MIGHT AS WELL BE SPRING... State Fair\ IT WON'T LET US LEAVE... Evil Dead IT'S A LOVELY DAY... Call me Madam JUST AROUND THE RIVER BEND.. Pocahontas IT'S NEVER ENTERED MY MIND..Higher and Higher JUST WILD ABOUT HARRY.. Big Deal KEYS .. Passing Strange LADY'S MAID... Titanic LAY DOWN YOUR HEAD.. Violet LIGHT... The Adventures of Tom Sawyer LOOK FOR A SILVER LINING. Till the Clouds roll by LOOK TO THE RAINBOW... Finian's Rainbow LOSING MY MIND.. Fossee LOVE... Love me Tonight LOVE MAKES THE WORLD GO ROUND.. Carnival LOVE NEVER DIES... Love Never Dies LOVE'S NEVER EASY... Bombay Dreams LULLABY OF BROADWAY... 42nd Street MACAROONS... Acorn Antiques MELTING MOGGY... Honk MISTER RIGHT... Love Life MOLL'S SONG... The Cradle Will Rock MY FUNNY VALENTINE... Babes in Arms MY OWN MORNING... Halleelujah Baby NINE PEOPLE'S FAVORITE THING.. Title of Show NO OTHER LOVE.. Me and Juliet NOBODY'S SIDE... Chess NOT SINCE NINEVEH... Kismet 100 WAYS TO LOSE A MAN.. Wonderful Town OOH! MY FEET... The most happy fella ONCE UPON A DECEMBER.... Anastasia\ ONE DAY I'LL FLY AWAY.. Moulin Rouge ONE NIGHT ONLY.. Dream Girls PARIS BY NIGHT.. Victor Victoria PASSONATE and TRUE..The Addams Family MUsical. PURLIE... Purlie RAGS... Rags RAIN ON THE ROOF.. The Wild Party ROLL IN THE HAY.. The Young Frankenstein SECOND STAR TO THE RIGHT... Peter Pan SHINE... Billy Elliot SEPTEMBER SONG... Lovemusik SOME DAY.. The Wedding Singer T'AINT NOBODY'S BUSINESS.. Black and Blue THANK GOD I'M OLD... Barnum THE BARE NECESSITIES... The Jungle Book THE CALLING.. Altar Boyz THE GARDEN RAM... Two by Two THE MAN I LOVE.. Strike up the Band TO KEEP MY LOVE ALIVE.. Connecticut Yankee TOO MANY RINGS AROUND ROSIE.. No, No Nanette UNDER THE TREE.. Celebration YOU TOOK ADVANTAGE of me.. On Your Toes WAITING FOR LIFE...Once upon this Island WITH ONE LOOK.. Sunset Boulevard WORDS, WORDS, WORDS.. Witches of Eastwick YOU'LL NEVER BE ALONE.A Tale of Two Cities

All the Things You Are is great. Listen to this version from the original show. (The sheet music is a step or half step lower.)