Roboguru

Diketahui persamaan termokimia berikut.       Entalpi reaksi :   adalah ....

Pertanyaan

Diketahui persamaan termokimia berikut.
 

table attributes columnalign right center left columnspacing 0px end attributes row cell C open parentheses italic s close parentheses and O subscript 2 open parentheses italic g close parentheses end cell rightwards arrow cell C O subscript 2 open parentheses italic g close parentheses space increment H equals minus sign 393 comma 52 space kJ end cell row cell H subscript 2 open parentheses italic g close parentheses plus begin inline style bevelled 1 half end style O subscript 2 open parentheses italic g close parentheses end cell rightwards arrow cell H subscript 2 O open parentheses italic l close parentheses space increment H equals minus sign 285 comma 83 space kJ end cell row cell C open parentheses italic s close parentheses and 2 H subscript 2 open parentheses italic g close parentheses end cell rightwards arrow cell C H subscript 4 open parentheses italic g close parentheses space increment H equals minus sign 74 comma 81 space kJ end cell end table 
 

Entalpi reaksi :

table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C H subscript 4 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell plus 2 O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank rightwards arrow blank end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank plus end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell 2 H subscript 2 O open parentheses italic l close parentheses end cell end table 

adalah .... 

  1. -890,37 kJ

  2. -796, 52 kJ

  3. -596,55 kJ

  4. -59,67 kJ

  5. -57,45 kJ

Pembahasan Soal:

Hukum Hess menyatakan bahwa "jika suatu proses dapat berlangsung melalui beberapa tahapan, perubahan entalpi keseluruhan adalah sama, tidak peduli tahapan mana yang dilalui".

Penentuan perubahan entalpi reaksi table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C H subscript 4 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell plus 2 O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank rightwards arrow blank end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank plus end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell 2 H subscript 2 O open parentheses italic l close parentheses end cell end table dapat dihitung berdasarkan data seluruh entalpi pada semua reaksi sebagai berikut.

C open parentheses italic s close parentheses and O subscript 2 open parentheses italic g close parentheses rightwards arrow C O subscript 2 open parentheses italic g close parentheses space increment H equals minus sign 393 comma 52 space kJ space open parentheses tetap close parentheses H subscript 2 open parentheses italic g close parentheses plus begin inline style bevelled 1 half end style O subscript 2 open parentheses italic g close parentheses rightwards arrow H subscript 2 O open parentheses italic l close parentheses space increment H equals minus sign 285 comma 83 space kJ space left parenthesis tetap comma space cross times 2 right parenthesis C open parentheses italic s close parentheses and 2 H subscript 2 open parentheses italic g close parentheses rightwards arrow C H subscript 4 open parentheses italic g close parentheses space increment H equals minus sign 74 comma 81 space kJ space open parentheses tetap close parentheses  up diagonal strike C open parentheses italic s close parentheses end strike plus O subscript 2 open parentheses italic g close parentheses rightwards arrow C O subscript 2 open parentheses italic g close parentheses space increment H equals minus sign 393 comma 52 space kJ up diagonal strike 2 H subscript 2 open parentheses italic g close parentheses end strike plus O subscript 2 open parentheses italic g close parentheses rightwards arrow 2 H subscript 2 O open parentheses italic l close parentheses space increment H equals minus sign 571 comma 66 space kJ C H subscript 4 open parentheses italic g close parentheses rightwards arrow up diagonal strike C open parentheses italic s close parentheses end strike plus up diagonal strike 2 H subscript 2 open parentheses italic g close parentheses end strike space increment H equals plus 74 comma 81 space kJ C H subscript bold 4 bold open parentheses italic g bold close parentheses bold plus O subscript bold 2 bold open parentheses italic g bold close parentheses bold rightwards arrow C O subscript bold 2 bold left parenthesis italic g bold right parenthesis bold plus H subscript bold 2 O bold open parentheses italic l bold close parentheses bold space bold increment H bold equals bold minus sign bold 890 bold comma bold 37 bold space bold kJ

Berdasarkan perhitungan diatas, perubahan entalpi reaksi table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C H subscript 4 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell plus 2 O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank rightwards arrow blank end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell C O subscript 2 open parentheses italic g close parentheses end cell end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank plus end table table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell 2 H subscript 2 O open parentheses italic l close parentheses end cell end table sebesar -890,37 kJ.

Jadi, jawaban yang benar adalah A.

Pembahasan terverifikasi oleh Roboguru

Terakhir diupdate 19 Juli 2021

RUANGGURU HQ

Jl. Dr. Saharjo No.161, Manggarai Selatan, Tebet, Kota Jakarta Selatan, Daerah Khusus Ibukota Jakarta 12860

Coba GRATIS Aplikasi Ruangguru

Produk Ruangguru

Produk Lainnya

Hubungi Kami

Ikuti Kami

©2021 Ruangguru. All Rights Reserved